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Sample records for benzenedicarboxylic acid-ortho

  1. Ionothermal synthesis, structures, properties of cobalt-1,4-benzenedicarboxylate metal-organic frameworks

    Science.gov (United States)

    Zhang, Zong-Hui; Xu, Ling; Jiao, Huan

    2016-06-01

    Eight kinds of 1-methyl-3-alkylimidazolium halide [RMI]X (R=ethyl (E), propyl (P), butyl (B) and amyl (A); MI = imidazolium; X= Cl-, I-) ionic liquids (ILs) were used as reaction media and obtained a series of 2D [RMI]2[Co3(BDC)3X2] frameworks through the ionothermal reactions of 1,4-benzenedicarboxylic acid (H2BDC) with Co(NO3)2·6H2O. The 2D [RMI]2[Co3(BDC)3X2] frameworks exhibit a same (3,6) topology network with [RMI]+ cations locating in the interlayer space. [RMI]+ cations play a template role in the structure constructions, whose influence combining with the effect of X- anions pass to the TG behaviors. The decomposition temperatures of the [RMI]2[Co3(BDC)3X2] frameworks decrease with the alkyl chains in [RMI]+ cations, and the compounds containing Cl- show higher thermal stabilities than those with I-. However, compounds 1-8 exhibit two similar broad emissions at ca. 380 and 390 nm, assigned to ILCT. The RMI+ templates and the X- anions do not exert their influence on the fluorescence.

  2. Tuning zinc coordination architectures by benzenedicarboxylate position isomers and bis(triazole)

    Science.gov (United States)

    Peng, Yan-fen; Li, Ke; Zhao, Shan; Han, Shan-shan; Li, Bao-long; Li, Hai-Yan

    2015-08-01

    Three position isomers 1,2-, 1,3-, 1,4-benzenedicarboxylate and 1,4-bis(1,2,4-triazol-4-yl)benzene were used to assembly zinc(II) coordination polymers {[Zn2(btx)0.5(1,2-bdc)2(H2O)]·H2O}n (1), {[Zn(btx)(1,3-bdc)]·2H2O·(DMF)}n (2) and {[Zn(btx)(1,4-bdc)]·3H2O}n (3). 1 is a (3,4,4,4)-connected two-dimensional network with point symbol (42·6)(44·62)(43·62·8)(42·6·103). 2 shows a two-dimensional (4,4) network. 3 exhibits a 5-fold interpenetrated three-dimensional diamondoid network. The structural versatility shows that the structures of coordination polymers can be tuned by the position isomers ligands. The luminescence and thermal stability were investigated.

  3. Surfactant-assisted facile synthesis of fluorescent zinc benzenedicarboxylate metal-organic framework nanorods with enhanced nitrobenzene explosives detection

    International Nuclear Information System (INIS)

    Graphical abstract: The present work describes a surfactant-assisted synthesis of nanoscale metal-organic framework (NMOF), and fluorescent sensing of nitrobenzene. The results suggest that the presence of the surfactant is crucial to the formation of NMOF with uniform size and shape, and significant quenching of fluorescent NMOFs may be monitored to detect nitroaromatic explosives. Highlights: ► Zn-BDC MOF (BDC = 1,4-benzenedicarboxylate) nanorods were readily synthesized via a CTAB surfactant assisted methodology. ► CTAB surfactant plays an essential role in the formation of Zn-BDC MOF nanorods, while has no effect on its phase formation. ► Zn-BDC nanorods exhibit superior nitrobenzene sensing properties over its counter micro-scaled crystals obtained without the presence of CTAB surfactant. - Abstract: Zinc benzenedicarboxylate (Zn-BDC, BDC = 1,4-benzenedicarboxylate) nanorods were synthesized via a novel cetyl trimethylammonium bromide (CTAB) surfactant-assisted technique and characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and fluorescent sensing of nitrobenzene, respectively. The XRD analysis reveals that the products obtained with or without CTAB surfactant are both crystalline Zn-BDC MOF with a 2D layered structure. SEM images show that, in the presence of CTAB surfactant, Zn-BDC MOF nanosheets formed initially and were then transformed into Zn-BDC MOF nanorods with the increase of the reaction time. In contrast, micro-sized particles of Zn-BDC MOF with irregular shape formed in the absence of CTAB surfactant. It was found that Zn-BDC MOF nanorods exhibit superior nitrobenzene sensing properties over its counter part: micro-sized particles.

  4. Synthesis, Structures and Properties of Two Metal-organic Frameworks Derived from 3-Nitro-1,2-benzenedicarboxylic Acid

    International Nuclear Information System (INIS)

    Two metal-organic frameworks based on the connectivity co-effect between rigid benzenedicarboxylic acid and bridging ligand have been synthesized [Zn2(3-NO2-bdc)2(4,4'-bpy)2H2O]n (1), [Co(3-NO2-bdc)(4,4'-bpy)H2O]n (2) (where 3-NO2-bdcH2 = 3-nitro-1,2-benzenedicarboxylic acid, 4,4'-bpy = 4,4'-bipyridine). The two novel complexes were characterized by IR spectrum, elemental analysis, fluorescent properties, thermogravimetric analysis, single-crystal X-ray diffraction and powder X-ray diffraction (PXRD). X-ray structure analysis reveals that 1 and 2 are two-dimensional (2D) network structures. Complex 1 and complex 2 belong to triclinic crystal with P-1 space group. The luminescence measurements reveal that two complexes exhibit good fluorescent emissions in the solid state at room temperature. Also, thermal decomposition process and powder X-ray diffraction of complexes were investigated

  5. Adsorptive removal of methyl orange from aqueous solution with metal-organic frameworks, porous chromium-benzenedicarboxylates

    International Nuclear Information System (INIS)

    Two typical highly porous metal-organic framework (MOF) materials based on chromium-benzenedicarboxylates (Cr-BDC) obtained from Material of Institute Lavoisier with special structure of MIL-101 and MIL-53 have been used for the adsorptive removal of methyl orange (MO), a harmful anionic dye, from aqueous solutions. The adsorption capacity and adsorption kinetic constant of MIL-101 are greater than those of MIL-53, showing the importance of porosity and pore size for the adsorption. The performance of MIL-101 improves with modification: the adsorption capacity and kinetic constant are in the order of MIL-101 < ethylenediamine-grafted MIL-101 < protonated ethylenediamine-grafted MIL-101 (even though the porosity and pore size are slightly decreased with grafting and further protonation). The adsorption capacity of protonated ethylenediamine-grafted MIL-101 decreases with increasing the pH of an aqueous MO solution. These results suggest that the adsorption of MO on the MOF is at least partly due to the electrostatic interaction between anionic MO and a cationic adsorbent. Adsorption of MO at various temperatures shows that the adsorption is a spontaneous and endothermic process and that the entropy increases (the driving force of the adsorption) with MO adsorption. The adsorbent MIL-101s are re-usable after sonification in water. Based on this study, MOFs can be suggested as potential re-usable adsorbents to remove anionic dyes because of their high porosity, facile modification and ready re-activation.

  6. Combination effect of ionic liquid components on the structure and properties in 1,4-benzenedicarboxylate based zinc metal-organic frameworks.

    Science.gov (United States)

    Zhang, Zong-Hui; Liu, Bing; Xu, Ling; Jiao, Huan

    2015-11-01

    Two types of 2D [RMI]2[Zn3(BDC)3X2] (Type A) and 3D [Zn(BDC)(H2O)] (Type B) (H2BDC = 1,4-benzenedicarboxylate acid) compounds were synthesized with three kinds of 1-alkyl-3-methyl imidazolium halide ([RMI]X) ionic liquids. Type A is the primary structure model showing a (3,6) network. Type B can be obtained from [BMI]Cl, [AMI]Cl and [AMI]Br media, showing a 4,4-connected {4(2)·8(4)} network. The structure, TG, and fluorescence analyses demonstrate the combination effect of the RMI(+) templating effect and X(-) controlling the structure types. The boundary between Types A and B is from [PMI]Cl, via [BMI]Br, to [AMI]I as the reaction media. The decomposition temperatures of the compounds in Type A decrease with increased RMI(+), while X(-) anions exert the influence that compounds containing Br(-) supply the highest thermal stability. Similarly, with increased RMI(+), or X = I(-), the compounds show red shifts compared to the emissions of the ligand. PMID:26402432

  7. Synthesis,Structure and Luminescence of Two Coordination Polymers Based on 1,4-Benzenedicarboxylate and 2-(3-Pyridyl)benzimidazole Ligands

    Institute of Scientific and Technical Information of China (English)

    LI wei; LI Ming-Xing; HE Xiang; SHAO Min; AN Bao-Li

    2008-01-01

    Hydrothermal reactions of Cd(Ⅱ)/Zn(Ⅱ)nitrates with 1,4-benzenedicarboxylic acid(H2Bdc)and 2-(3-pyridyl)-benzimidazole(3-PyHBIm)afforded complexes {[Cd(3-PyHBlm)(Bdc)(H2O)2](H2Bdc)1/2]n(1)and [Zn(3-PyHBIm)2-(Bdc)(H2O)2]n(2).X-ray structural analysis reveals that both complexes are ID coordination polymers.In complex 1,3-PyHBIm coordinates to Cd(Ⅱ)unidentately via a pyridyl N-donor.Bdc2-anion acts as a tetradentate ligand and coordinates to Cd(Ⅱ)to form a zigzag chain where two H2O coordinate in cis-fashion.H2Bdc guest molecule is involved in the hydrogen-bonding network,which leads to a 3D supramolecular architecture.In complex 2,Bdc2-acts as a bidentate ligand and coordinates to Zn(Ⅱ)to form a linear infinite chain where two H2O molecules coordi-nate in trans-fashion.The complexes are thermally stable and exhibit luminescence in the solid state.

  8. Two Unusual Two-dimensional (4,4) Network Cadmium Coordination Polymers Based on Flexible Bis(triazole) and Rigid Benzenedicarboxylate Co-ligands

    Institute of Scientific and Technical Information of China (English)

    孙鹏鹏; 赵珊; 杨志; 李宝龙; 吴冰

    2012-01-01

    Two cadmium(II) coordination polymers {[Cd(btp)(NO2-1,3-bdc)(H2O)]·H2O}n (1) and {[Cd(btp)(1,2-bdc)(H2O)]·H2O}n (2) were synthesized by the reaction of 1,3-bis(1,2,4-triazol-1-yl)propane (btp), 5-nitroisophthalate (NO2-1,3-bdc), and 1,2-benzenedicarboxylate (1,2-bdc). 1 consists of undulated 2D (4,4) networks. Two identical undulated layers are parallel stacking to give a (2D→2D) polythreaded 2D network. A 3D supramolecular architectute is constructed through the hydrogen bond interactions. 2 has an unusual 2D (4,4) network with a thickness of ca. 10A. The btp ligands exhibit the anti-gauche conformation in 1 and the anti-anti conformation in 2. The flexible btp ligand exhibits the key role in the assembly of the topologies of 1 and 2. The luminescence and thermal stability were investigated.

  9. Hydrothermal crystal growth and Vernier structures of the metal benzenedicarboxylates MIL-47 and MIL-53 containing guest molecules of benzenecarboxylic acid

    Science.gov (United States)

    Wang, Xiqu; Jacobson, Allan J.

    2016-04-01

    The nanoporous frameworks VO(bdc), MIL-47, and M(OH)(bdc), MIL-53; bdc=1,4-benzenedicarboxylate, can absorb various guest species in their channels. As synthesized, the channels are filled with H2bdc molecules that have been reported to be disordered, except for [In(OH)bdc](H2bdc)3/4, 1, which has a inorganic-organic hybrid Vernier structure with the H2bdc molecules forming an ordered sublattice. Based on X-ray data from large single crystals grown by hydrothermal techniques, similar Vernier structures have been found for MIL-47, [VO(bdc)](H2bdc)5/7, 2, MIL-53Al, [Al(OH)(bdc)](H2bdc)11/16, 3, and MIL-53Ga, [Ga(OH)(bdc)](H2bdc)12/17, 4. The Vernier structures of 2-4 at room temperature were determined based on superstructure unit cells that index both host and guest sublattices: 2, space group P21, a=23.903(2), b=17.191(2), c=25.722(2) Å, β=105.914(8)°; 3, P21/n, a=105.224(4), b=12.2441(5), c=17.0143(6) Å, β=89.99(1)°; 4, P21, a=114.562(5), b=12.1503(5), c=17.4275(7) Å, β=89.99(1)°. The number of guest H2bdc molecules per framework metal ion is determined by the ratio of the repeat distances of the two sublattices which depends on the size of the metal ion in the octahedral chain. The octahedral chains are parallel to [201] in 2, and to [100] in 3 and 4. Remarkably, all atoms in 3 and 4 show significant sinusoidal modulations transverse to the chain axis.

  10. Assembly of 1D, 2D and 3D lanthanum(iii) coordination polymers with perchlorinated benzenedicarboxylates: positional isomeric effect, structural transformation and ring-opening polymerisation of glycolide.

    Science.gov (United States)

    Chen, Sheng-Chun; Dai, An-Qi; Huang, Kun-Lin; Zhang, Zhi-Hui; Cui, Ai-Jun; He, Ming-Yang; Chen, Qun

    2016-02-28

    Utilizing a series of positional isomers of tetrachlorinated benzenedicarboxylic acid ligands, seven La(iii)-based coordination polymers were solvothermally synthesized and structurally characterized. Their structural dimensionalities varying from 1D double chains, to the 2D 3,4,5-connected network, to 3D 6-connected pcu topological nets are only governed by the positions of carboxyl groups on the tetrachlorinated benzene ring. A comprehensive analysis and comparison reveals that the size of the carbonyl solvent molecules (DMF, DEF, DMA, and NMP) can affect the coordination geometries around the La(iii) ions, the coordination modes of carboxylate groups, the packing arrangements, and the void volumes of the overall crystal lattices. One as-synthesized framework further shows an unprecedented structural transformation from a 3D 6-connected network to a 3D 4,5-connected net through the dissolution and reformation pathway in water, suggesting that these easily hydrolyzed lanthanide complexes may serve as precursors to produce new high-dimensional frameworks. The bulk solvent-free melt polymerisation of glycolide utilizing these La(iii) complexes as initiators has been reported herein for the first time. All complexes were found to promote the polymerization of glycolide over a temperature range of 200 to 220 °C, producing poly(glycolic acid) (PGA) with a molecular weight up to 93,280. Under the same experimental conditions, the different catalytic activities for these complexes may result from their structural discrepancy. PMID:26811117

  11. Construction of Six Coordination Polymers Based on a 5,5′-(1,2-Ethynyl)bis-1,3-benzenedicarboxylic Ligand: Synthesis, Structure, Gas Sorption, and Magnetic Properties

    KAUST Repository

    Zheng, Bing

    2013-03-06

    Six novel coordination polymers based on a multifunctional ligand, 5,5\\'-(1,2-ethynyl)bis-1,3-benzenedicarboxylic (H4EBDC), namely, |(C3H7NO)2(H2O)7(C 2H5OH)3| [Zn2(C18H 6O8)(C10H8N2) 2] (1), |(C3H7NO)3(H2O)30- (CH3CN)2|[Zn 6(C18H6O8)3(C 6H12N2O2)2] (2), |(C 3H7NO)2- (H2O)2(H 3O)2|[Cd3(C18H6O 8)2] (3), |(C3H7NO)|[Mn- (C 18H8O8)(C3H7NO) 2] (4), |(C3H7NO)2(H2O)(C 2H7N)3| [Mn6(C18H 7O8)4(H2O)8] (5), and [Mn2(C18H6O8)(C3H 7NO)2] (6), have been constructed under solvothermal conditions and structurally characterized by single-crystal X-ray diffraction. In these compounds, the ligand, H4EBDC, exhibits different coordination modes and conformations, constructing various architectures by bridging a variety of metal ions or polynuclear clusters. Compound 1 forms a three-dimensional (3D) FSC network constructed from two-dimensional (2D) layer motifs joined by EBDC4- and 4,4\\'-bipyridine bridges. Compound 2 possesses an NbO topology by linking Zn2(CO2)4 units with the ligand, coordinated amine molecules fill the pores, while compound 3 exhibits a 3D FLU network with Cd2+ as the cation and features an infinite framework built from tricadmium clusters. Compound 4 is based on PtS net, constructed of 4-connected rectangular H4EBDC units with tetrahedral monometallic Mn(CO2)4 nodes. Compound 5 is composed of 2D layers with (3,6)-connected KGD topology, and compound 6 consists of a 3D PtS-X network, built by bridging a metal chain with the ligand. The structures of these compounds have been discussed together with their corresponding properties, such as gas storage, separation, and magnetic properties. © 2013 American Chemical Society.

  12. Remarkable adsorptive performance of a metal-organic framework, vanadium-benzenedicarboxylate (MIL-47), for benzothiophene.

    Science.gov (United States)

    Khan, Nazmul Abedin; Jun, Jong Won; Jeong, Jong Hwa; Jhung, Sung Hwa

    2011-01-28

    Liquid-phase adsorption of benzothiophene over isotypic MOFs such as MIL-47 and MIL-53(Al, Cr) has shown that a metal ion of a MOF-type material has a dominant role in adsorptive desulfurization and MIL-47 has a remarkable performance. PMID:21152546

  13. 76 FR 7703 - 1,4-Benzenedicarboxylic Acid, Dimethyl Ester, Polymer With 1,4-Butanediol, Adipic Acid, and...

    Science.gov (United States)

    2011-02-11

    ...), minimum number average molecular weight (in amu) 30,000, when used as an inert ingredient (component of... average molecular weight (MW) greater than or equal to 10,000 daltons. Additionally, in order to meet the... nontoxic to earthworms. Due to its large size (minimum number average molecular weight 30,000 amu) and...

  14. 40 CFR 721.10072 - Benzene, 1,1′-methylenebis[4-isocyanato-, polymer with benzenedicarboxylic acid, butyl dialkyl...

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Benzene, 1,1â²-methylenebis , .alpha... SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.10072 Benzene, 1,1′-methylenebis... to reporting. (1) The chemical substance identified generically as benzene,...

  15. Anti-Human Immunodeficiency Virus Type 1 Microbicide Cellulose Acetate 1,2-Benzenedicarboxylate in a Human In Vitro Model of Vaginal Inflammation

    OpenAIRE

    Fichorova, R. N.; Zhou, F.(Central China Normal University, Wuhan, China); Ratnam, V.; Atanassova, V.; Jiang, S; Strick, N; Neurath, A R

    2005-01-01

    The sexual transmission of human immunodeficiency virus type 1 (HIV-1) is facilitated by inflammation and related epithelial barrier perturbation. Microbicides for vaginal applications are currently being developed to reduce the risk of HIV-1 transmission. However, little is known about their interference with epithelial immune function. In recent clinical trials, nonoxynol-9 (N-9), a virucide with a long history of intravaginal use as a contraceptive, failed to protect against HIV-1 possibly...

  16. 40 CFR 180.567 - Zoxamide; tolerances for residues.

    Science.gov (United States)

    2010-07-01

    ...-dichloro-1,4-benzenedicarboxylic acid (RH-1455 and RH-141455) and 3,5-dichloro-4-hydroxymethylbenzoic acid (RH-1452 and RH-141452) in or on the following commodities: Commodity Parts per million Potato...

  17. Syntheses and characterizations of three acid-base supramolecular complexes

    International Nuclear Information System (INIS)

    Three acid-base compounds with supramolecular architectures, namely, (1,2-H2bdc)(dmt) (1), (trans-1,4-H2ccdc)0.5(phdat) (2) and (1,3-H2bdc)(phdat) (3) (1,2-H2bdc = 1,2-benzenedicarboxylic acid, trans-1, 4-H2ccdc = trans-1, 4-cyclohexanedicarboxylic acid, 1,3-H2bdc = 1,3-benzenedicarboxylic acid, dmt = 2,4-diamino-6-methyl-s-triazine, phdat = 2,4-diamino-6-phenyl-s-triazine) have been synthesized and characterized by IR spectra, elemental analyses, single-crystal X-ray diffractions and TGA. (author)

  18. A new family of anionic organic–inorganic hybrid doughnut-like nanostructures

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Zhuxiu; Gao, Wen-Yang; Wojtas, Lukasz; Zhang, Zhenjie; Zaworotko, Michael J. (Limerick); (USF)

    2015-06-15

    A family of soluble organic–inorganic hybrid doughnut-like anions, hydoughnuts, has been prepared by the self-assembly of polyoxovanadate anions and 1,3-benzenedicarboxylate (bdc) linkers. Derivatives of the parent hydoughnut, [(V₄O₈Cl)₄(bdc)₈]⁴⁻, can be obtained by changing the counter-ion or by using a variant of bdc.

  19. Compositional control of pore geometry in multivariate metal-organic frameworks: an experimental and computational study.

    Science.gov (United States)

    Cadman, Laura K; Bristow, Jessica K; Stubbs, Naomi E; Tiana, Davide; Mahon, Mary F; Walsh, Aron; Burrows, Andrew D

    2016-03-14

    A new approach is reported for tailoring the pore geometry in five series of multivariate metal–organic frameworks (MOFs) based on the structure [Zn2(bdc)2(dabco)] (bdc = 1,4-benzenedicarboxylate, dabco = 1,8-diazabicyclooctane), DMOF-1. A doping procedure has been adopted to form series of MOFs containing varying linker ratios. The series under investigation are [Zn2(bdc)(2-x)(bdc-Br)x(dabco)]·nDMF 1 (bdc-Br = 2-bromo-1,4-benzenedicarboxylate), [Zn2(bdc)(2-x)(bdc-I)x(dabco)]·nDMF 2 (bdc-I = 2-iodo-1,4-benzenedicarboxylate), [Zn2(bdc)(2-x)(bdc-NO2)x(dabco)]·nDMF 3 (bdc-NO2 = 2-nitro-1,4-benzenedicarboxylate), [Zn2(bdc)(2-x)(bdc-NH2)x(dabco)]·nDMF 4 (bdc-NH2 = 2-amino-1,4-benzenedicarboxylate) and [Zn2(bdc-Br)(2-x)(bdc-I)x(dabco)]·nDMF 5. Series 1-3 demonstrate a functionality-dependent pore geometry transition from the square, open pores of DMOF-1 to rhomboidal, narrow pores with increasing proportion of the 2-substituted bdc linker, with the rhomboidal-pore MOFs also showing a temperature-dependent phase change. In contrast, all members of series 4 and 5 have uniform pore geometries. In series 4 this is a square pore topology, whilst series 5 exhibits the rhomboidal pore form. Computational analyses reveal that the pore size and shape in systems 1 and 2 is altered through non-covalent interactions between the organic linkers within the framework, and that this can be controlled by the ligand functionality and ratio. This approach affords the potential to tailor pore geometry and shape within MOFs through judicious choice of ligand ratios. PMID:26660286

  20. Acid hydrolysis of kallar grass (leptochloa fusca) for the production

    International Nuclear Information System (INIS)

    Acid hydrolysis of kallar grass (leptochloa fusca) was carried of with various concentrations of sulphuric acid, ortho phosphoric acid and hydrochloric acid to produce furfural. The study revealed that activity of various hydrolysing acids to produce furfural from kallar grass was of the following order H/sub 2/SO/sub 4/ > H/sub 3/PO/sub 4/ > HCl. Optimum yield (4.78%) of the produce was obtained when the material was digested with 19% H/sub 2/SO/sub 4/ for a period of 20 minutes. (author)

  1. Gated Channels and Selectivity Tuning of CO2 over N2 Sorption by Post-Synthetic Modification of a UiO-66-Type Metal-Organic Framework.

    Science.gov (United States)

    Kronast, Alexander; Eckstein, Sebastian; Altenbuchner, Peter T; Hindelang, Konrad; Vagin, Sergei I; Rieger, Bernhard

    2016-08-26

    The highly porous and stable metal-organic framework (MOF) UiO-66 was altered using post-synthetic modifications (PSMs). Prefunctionalization allowed the introduction of carbon double bonds into the framework through a four-step synthesis from 2-bromo-1,4-benzenedicarboxylic acid; the organic linker 2-allyl-1,4-benzenedicarboxylic acid was obtained. The corresponding functionalized MOF (UiO-66-allyl) served as a platform for further PSMs. From UiO-66-allyl, epoxy, dibromide, thioether, diamine, and amino alcohol functionalities were synthesized. The abilities of these compounds to adsorb CO2 and N2 were compared, which revealed the structure-selectivity correlations. All synthesized MOFs showed profound thermal stability together with an increased ability for selective CO2 uptake and molecular gate functionalities at low temperatures. PMID:27483397

  2. Thermodynamics of the Oxygen Evolution Electrocatalysis in Metal-Organic Frameworks

    OpenAIRE

    Musho, Terence; Li, Jiangtan; Wu, Nianqiang

    2015-01-01

    Metal-organic frameworks (MOFs) provide a versatile and tailorable material platform that embody many desirable attributes for photocatalytic water-splitting. The approach taken in this study was to use Density Functional Theory (DFT) to predict the thermodynamic energy barriers of the oxygen evolution reaction (OER) for three MOF functionalizations. A Zr-MIL-125 MOF design was selected for this study that incorporates three linker designs, a 1,4-benzenedicarboxylate (BDC), BDC functionalized...

  3. The Role of Benzoate in Anaerobic Degradation of Terephthalate

    OpenAIRE

    Kleerebezem, Robbert; Pol, Look W. Hulshoff; Lettinga, Gatze

    1999-01-01

    The effects of acetate, benzoate, and periods without substrate on the anaerobic degradation of terephthalate (1,4-benzene-dicarboxylate) by a syntrophic methanogenic culture were studied. The culture had been enriched on terephthalate and was capable of benzoate degradation without a lag phase. When incubated with a mixture of benzoate and terephthalate, subsequent degradation with preference for benzoate was observed. Both benzoate and acetate inhibited the anaerobic degradation of terephth...

  4. Biocompatibility of Solid-Dosage Forms of Anti-Human Immunodeficiency Virus Type 1 Microbicides with the Human Cervicovaginal Mucosa Modeled Ex Vivo▿

    OpenAIRE

    Trifonova, Radiana T.; Pasicznyk, Jenna-Malia; Fichorova, Raina N.

    2006-01-01

    Topical anti-human immunodeficiency virus (HIV) microbicides are being sought to reduce the spread of HIV type 1 (HIV-1) during sexual intercourse. The success of this strategy depends upon the selection of formulations compatible with the natural vaginal mucosal barrier. This study applied ex vivo-modeled human cervicovaginal epithelium to evaluate experimental solid-dosage forms of the anti-HIV-1 microbicide cellulose acetate 1,2-benzenedicarboxylate (CAP) and over-the-counter (OTC) vaginal...

  5. THE IMPACT OF PHTHALATE ESTERS IN THE ENVIRONMENTAL AND HUMAN HEALTH – ARE THESE COMPOUNDS, A NECESSARY EVIL?

    OpenAIRE

    DOS SANTOS, Marcel Silveira

    2011-01-01

    Phthalates are a group of diesters of phthalic acid (dialkyl or alkyl aryl esters of 1,2-benzenedicarboxylic acid) and they are primarily used as plasticizers (substances added to plastics to increase their flexibility). As the phthalates are not chemically bonded to the polymer, these compounds can migrate from the plastic material to the environment and, consequently, they are found in food, water, soil, air and in the human body. This article discusses the problem of using those compoun...

  6. Di-(2-ethylhexyl phthalate and autism spectrum disorders

    Directory of Open Access Journals (Sweden)

    Giuseppe Latini

    2012-05-01

    Full Text Available ASDs (autism spectrum disorders are a complex group of neurodevelopment disorders, still poorly understood, steadily rising in frequency and treatment refractory. Extensive research has been so far unable to explain the aetiology of this condition, whereas a growing body of evidence suggests the involvement of environmental factors. Phthalates, given their extensive use and their persistence, are ubiquitous environmental contaminants. They are EDs (endocrine disruptors suspected to interfere with neurodevelopment. Therefore they represent interesting candidate risk factors for ASD pathogenesis. The aim of this study was to evaluate the levels of the primary and secondary metabolites of DEHP [di-(2-ethylhexyl phthalate] in children with ASD. A total of 48 children with ASD (male: 36, female: 12; mean age: 11±5 years and age- and sex-comparable 45 HCs (healthy controls; male: 25, female: 20; mean age: 12±5 years were enrolled. A diagnostic methodology, based on the determination of urinary concentrations of DEHP metabolites by HPLC-ESI-MS (HPLC electrospray ionization MS, was applied to urine spot samples. MEHP [mono-(2-ethylhexenyl 1,2-benzenedicarboxylate], 6-OH-MEHP [mono-(2-ethyl-6-hydroxyhexyl 1,2-benzenedicarboxylate], 5-OH-MEHP [mono-(2-ethyl-5-hydroxyhexyl 1,2-benzenedicarboxylate] and 5-oxo-MEHP [mono-(2-ethyl-5-oxohexyl 1,2-benzenedicarboxylate] were measured and compared with unequivocally characterized, pure synthetic compounds (>98% taken as standard. In ASD patients, significant increase in 5-OH-MEHP (52.1%, median 0.18 and 5-oxo-MEHP (46.0%, median 0.096 urinary concentrations were detected, with a significant positive correlation between 5-OH-MEHP and 5-oxo-MEHP (rs = 0.668, P<0.0001. The fully oxidized form 5-oxo-MEHP showed 91.1% specificity in identifying patients with ASDs. Our findings demonstrate for the first time an association between phthalates exposure and ASDs, thus suggesting a previously unrecognized role for

  7. Phytochemical and Biological Studies of Agave attenuata

    OpenAIRE

    Vincenzo De Feo; Muhammad Riaz; Nasir Rasool; Muhammad Zubair; Komal Rizwan; Muhammad Zia-Ul-Haq

    2012-01-01

    The present study was conducted to examine various biological activities of a methanol extract of Agave attenuata leaves. GC-MS analysis of the n-hexane fraction from the extract revealed the presence of 31 compounds, with mono-2-ethylhexyl phthalate (11.37%), 1,2-benzenedicarboxylic acid (6.33%), n-docosane (6.30%) and eicosane (6.02%) as the major components. The leaves contained appreciable levels of total phenolic contents (10...

  8. Mixed ligand coordination polymer based on 5-nitroisophthalic acid and 1-(4-nitrophenyl)-1,2,4-triazole: Synthesis, characterization, magnetic and photocatalytic properties

    Science.gov (United States)

    Li, Le; Ju, Wen-Wen; Tao, Jian-Qing; Xin, Rong; Wang, Jun; Xu, Xiao-Juan

    2015-09-01

    A new Cu(II) coordination polymer, namely, [Cu(NPT)2(NO2-BDC)]n (1) (NO2-H2BDC = 5-nitro-1,3-benzenedicarboxylic acid, NPT = 4-(4-nitrophenyl)-1,2,4-triazole) has been synthesized under hydrothermal condition and characterized by elemental analysis, and single-crystal X-ray diffraction. Single-crystal X-ray diffraction study reveals that complex 1 features one-dimensional chain structure. The magnetic studies reveal that the antiferromagnetic interactions exist between the adjacent CuII ions. Moreover, complex 1 displays highly photocatalytic degradation activity for the degradation of rhodamine B, methylene blue and methyl orange.

  9. One-pot synthesis of a metal–organic framework as an anode for Li-ion batteries with improved capacity and cycling stability

    International Nuclear Information System (INIS)

    Metal–organic framework is a kind of novel electrode materials for lithium ion batteries. Here, a 3D metal–organic framework Co2(OH)2BDC (BDC=1,4-benzenedicarboxylate) was synthesized for the first time by the reaction of Co2+ with a bio-inspired renewable organic ligand 1,4-benzenedicarboxylic acid through a solvothermal method. As an anode material for lithium ion batteries, this material exhibited an excellent cyclic stability as well as a large reversible capacity of ca. 650 mA h g−1 at a current density of 50 mA g−1 after 100 cycles within the voltage range of 0.02–3.0 V, higher than that of other BDC based anode. - Graphical abstract: The PXRD pattern and the cycleability curves (inset) of Co2(OH)2BDC. Display Omitted - Highlights: • Co2(OH)2BDC was synthesized through a one pot solvothermal process. • The solvent had a great effect on the purity of this material. • This material was used as anode material for lithium ion batteries for the first time. • Co2(OH)2BDC showed improved capacity and cycling stability

  10. E-beam degradation of dibutyl phthalate

    International Nuclear Information System (INIS)

    E-beam degradation of dibutyl phthalate (DBP) in oxidation system (acetonitrile/water), reduction system (methanol/water, t-BuOH/water), and pure water systems was investigated. DBP concentration in the four solutions was determined by HPLC, and the degradation products were analyzed by GC/MS. The results showed that the DBP degradation followed pseudo-first-order kinetics. DBP in a concentration of 7.8mg/L, in all solutions but the t-BuOH/water, could be degraded in a rate of over 85% by 0.5 kGy E-beam irradiation. The degradation products included diethyl phthalate, bis(2-methylpropyl)ester, and 1,2-Benzenedicarboxylic acid in the three solutions. Finally, mechanism of the DBP degradation was discussed. (authors)

  11. Thermodynamics of the Oxygen Evolution Electrocatalysis in Metal-Organic Frameworks

    CERN Document Server

    Musho, Terence; Wu, Nianqiang

    2015-01-01

    Metal-organic frameworks (MOFs) provide a versatile and tailorable material platform that embody many desirable attributes for photocatalytic water-splitting. The approach taken in this study was to use Density Functional Theory (DFT) to predict the thermodynamic energy barriers of the oxygen evolution reaction (OER) for three MOF functionalizations. A Zr-MIL-125 MOF design was selected for this study that incorporates three linker designs, a 1,4-benzenedicarboxylate (BDC), BDC functionalized with an amino group (BDC+NH2), and BDC functionalized with nitro group (BDC+NO2). The study found several key differences between homogeneous planar catalyst thermodynamics and MOF based thermodynamics, the most significant being the non-unique or heterogeneity of reaction sites. Additionally, the funcationalization of the MOF was found to significantly influence the hydroperoxyl binding energy, which proves to be the largest hurdle for both oxide and MOF based catalyst. Both of these findings provide evidance that many ...

  12. Chemistry of clitoral gland secretions of the laboratory rat: Assessment of behavioural response to identified compounds

    Indian Academy of Sciences (India)

    S Kannan; G Archunan

    2001-06-01

    The present investigations were carried out to find out the chemical nature of clitoral gland extracts and their involvement in reproductive and social behaviour. Homogenates of clitoral glands of mature estrous female rats were extracted with -hexane and dichloromethane (1 : 1 ratio v/v) and analysed by gas chromatography linked mass spectrometry (GC-MS). Three peaks were found to be in higher concentration, which were identified as 6,11-dihydro-dibenz-b,e-oxepin-11-one (I); 2,6,10-dodecatrien-1-ol-3,7,11-trimethyl(Z) (II); and 1,2-benzene-dicarboxylic acid butyl(2-ethylpropyl) ester (III).Odour preference tests demonstrated that the first compound attracted conspecifics of the opposite sex. By contrast, the second and third compounds were found to attract both sexes. The results conclude that the clitoral gland of laboratory rat contains three major chemical compounds which have a unique function in maintaining social and reproductive status.

  13. Occurrence and spatial distribution of microplastics in sediments from Norderney.

    Science.gov (United States)

    Dekiff, Jens H; Remy, Dominique; Klasmeier, Jörg; Fries, Elke

    2014-03-01

    The spatial distribution of small potential microplastics (SPM) (1 mm) was also examined. Small microparticles were extracted from 36 one kg sediment samples and analysed by visual microscopic inspection and partly by thermal desorption pyrolysis gas chromatography/mass spectrometry. The smallest particle size that could be analysed with this method was estimated to be 100 μm. The mean number of SPM at the three sampling sites (n = 12) was 1.7, 1.3 and 2.3 particles per kg dry sediment, respectively. SPM were identified as polypropylene, polyethylene, polyethylene terephthalate, polyvinylchloride, polystyrene and polyamide. The organic plastic additives found were benzophenone, 1,2-benzenedicarboxylic acid, dimethyl phthalate, diethylhexyl phthalate, dibutyl phthalate, diethyl phthalate, phenol and 2,4-di-tert-butylphenol. Particles were distributed rather homogenously and the occurrence of SPM did not correlate with that of VPD. PMID:24448461

  14. Sonochemical Synthesis of Photoluminescent Nanoscale Eu(III-Containing Metal-Organic Frameworks

    Directory of Open Access Journals (Sweden)

    Cheng-an TAO

    2015-12-01

    Full Text Available Nanoscale lanthanide-containing metal-organic frameworks (MOFs have more and more interest due to their great properties and potential applications, but how to construct them easily is still challenging. Here, we present a facile and rapid synthesis of Eu(III-containing Nanoscale MOF (denoted as NMOF under ultrasonic irradiation. The effect of the ratio and the addition order of metal ions and linkers on the morphology and size of MOFs was investigated. It is found that both of the ratio and the addition order can affect the morphology and size of 1,4-benzenedicarboxylic acid(H2BDC -based MOFs, but they show no evident influence on that of H2aBDC-based MOFs. The former exhibit typical emission bands of Eu(III ions, while the latter only show the photoluminescent properties of ligands.

  15. Novel polythreaded coordination polymer: from an armed-polyrotaxane sheet to a 3D polypseudorotaxane array, photo- and thermochromic behaviors.

    Science.gov (United States)

    Yao, Qing-Xia; Ju, Zhan-Feng; Jin, Xu-Hui; Zhang, Jie

    2009-02-16

    A novel coordination compound, {[Cd(BDC)(Bpybc)(1.5)].10H(2)O}(n), obtained by the reaction of CdCl(2) with 1,1'-bis(4-carboxybenzyl)-4,4'-bipyridinium dichloride (H(2)BpybcCl(2)) and 1,4-benzenedicarboxylic acid (H(2)BDC), contains 1D polymeric chains that are comprised of alternating rings and rods and dangling lateral arms. These 1D polymeric motifs are interlaced via rotaxane-like mechanical linkages to give 2D armed-polyrotaxane sheets, which are further mutually polythreaded via pseudorotaxane-like mechanical linkages to form a 3D polypseudorotaxane array. Notably, a sandwich-type donor-acceptor-donor stacking is formed within each ring as a consequence of both types of polythreading in this species, and photoinduced and thermal-induced reduction of bipyridinium occurs with a color change from light yellow to blue. PMID:19166285

  16. Sonochemical Synthesis of Photoluminescent Nanoscale Eu(III-Containing Metal-Organic Frameworks

    Directory of Open Access Journals (Sweden)

    Cheng-an TAO

    2015-11-01

    Full Text Available Nanoscale lanthanide-containing metal-organic frameworks (MOFs have more and more interest due to their great properties and potential applications, but how to construct them easily is still challenging. Here, we present a facile and rapid synthesis of Eu(III-containing Nanoscale MOF (denoted as NMOF under ultrasonic irradiation. The effect of the ratio and the addition order of metal ions and linkers on the morphology and size of MOFs was investigated. It is found that both of the ratio and the addition order can affect the morphology and size of 1.4-benzenedicarboxylic acid(H2BDC -based MOFs, but they show no evident influence on that of H2aBDC-based MOFs. The former exhibit typical emission bands of Eu(III ions, while the latter only show the photoluminescent properties of ligands.DOI: http://dx.doi.org/10.5755/j01.ms.21.4.9695

  17. Structure and spectroscopy of hydrogen adsorbed in a nickel metal–organic framework

    International Nuclear Information System (INIS)

    Highlights: • D2 adsorbed in Ni2(dobdc) exhibits a close metal-D2 distance of 2.20(1) Å. • H2 quantum rotational levels determined for 3 adsorption sites. • Layering of H2 over D2 reveal the transitions of H2 at the second adsorption site. - Abstract: The structure of Ni2(dobdc) (dobdc4− = 2,5-dioxido-1,4-benzenedicarboxylate) as a function of deuterium adsorption has been determined through the application of in situ neutron powder diffraction. Detailed information concerning the local adsorption potential for hydrogen at each site has also been probed using inelastic neutron scattering techniques. These results are compared to those previously published on isostructural analogs and the Ni2+ variant shows the shortest deuterium-metal distance in the M2(dobdc) series (M = Mg, Zn, Co, Fe) that have been studied so far

  18. Elucidating Negative Thermal Expansion in MOF-5

    International Nuclear Information System (INIS)

    Multi-temperature X-ray diffraction studies show that twisting, rotation, and libration cause negative thermal expansion (NTE) of the nanoporous metal-organic framework MOF-5, Zn4O(1,4-benzenedicarboxylate)3. The near-linear lattice contraction is quantified in the temperature range 80-500 K using synchrotron powder X-ray diffraction. Vibrational motions causing the abnormal expansion behavior are evidenced by shortening of certain interatomic distances with increasing temperature according to single-crystal X-ray diffraction on a guest-free crystal over a broad temperature range. Detailed analysis of the atomic positional and displacement parameters suggests two contributions to cause the effect: (1) local twisting and vibrational motion of the carboxylate groups and (2) concerted transverse vibration of the linear linkers. The vibrational mechanism is confirmed by calculations of the dynamics in a molecular fragment of the framework.

  19. Solvothermal synthesis of Fe-MOF-74 and its catalytic properties in phenol hydroxylation.

    Science.gov (United States)

    Bhattacharjee, Samiran; Choi, Jung-Sik; Yang, Seung-Tae; Choi, Sang Beom; Kim, Jaheon; Ahn, Wha-Seung

    2010-01-01

    A Fe-containing metal-organic framework, Fe-MOF-74, was solvothermally synthesized using FeCl2.4H2O and 2,5-di-hydroxy-1,4-benzenedicarboxylic acid. Characterization was conducted by XRD, BET surface area measurement, FT-IR spectroscopy, TGA, and elemental analysis, which confirmed successful preparation of Fe-MOF-74 having an identical framework structure to that reported for MOF-74. Fe-MOF-74 was found to be an effective heterogeneous catalyst for the hydroxylation of phenol using H2O2 as an oxidant; 60% phenol conversion was achieved at 20 degrees C in water with 68 and 32% selectivity to catechol and hydroquinone, respectively. The effect of temperature, phenol/H2O2 mole ratio, catalyst quantity, and solvent on catalytic performance was discussed, and a reaction mechanism is proposed based upon the experimental results. PMID:20352823

  20. ALD/MLD processes for Mn and Co based hybrid thin films.

    Science.gov (United States)

    Ahvenniemi, E; Karppinen, M

    2016-06-28

    Here we report the growth of novel transition metal-organic thin-film materials consisting of manganese or cobalt as the metal component and terephthalate as the rigid organic backbone. The hybrid thin films are deposited by the currently strongly emerging atomic/molecular layer deposition (ALD/MLD) technique using the combination of a metal β-diketonate, i.e. Mn(thd)3, Co(acac)3 or Co(thd)2, and terephthalic acid (1,4-benzenedicarboxylic acid) as precursors. All the processes yield homogeneous and notably smooth amorphous metal-terephthalate hybrid thin films with growth rates of 1-2 Å per cycle. The films are stable towards humidity and withstand high temperatures up to 300 or 400 °C under an oxidative or a reductive atmosphere. The films are characterized with XRR, AFM, GIXRD, XPS and FTIR techniques. PMID:27277668

  1. Solid lithium electrolyte via addition of lithium salts to metal-organic frameworks

    Energy Technology Data Exchange (ETDEWEB)

    Wiers, Brian M.; Balsara, Nitash P.; Long, Jeffrey R.

    2016-03-29

    Various embodiments of the invention disclose that the uptake of LiO.sup.iPr in Mg.sub.2(dobdc) (dobdc.sup.4-=1,4-dioxido-2,5-benzenedicarboxylate) followed by soaking in a typical electrolyte solution leads to a new solid lithium electrolyte Mg.sub.2(dobdc).0.35LiO.sup.iPr.0.25LiBF.sub.4.EC.DEC. Two-point ac impedance data show a pressed pellet of this material to have a conductivity of 3.1.times.10.sup.-4 S/cm at 300 K. In addition, the results from variable-temperature measurements reveal an activation energy of approximately 0.15 eV, while single-particle data suggest that intraparticle transport dominates conduction.

  2. Histamine immunohistochemistry: a new and highly sensitive method for studying cutaneous mast cells.

    Science.gov (United States)

    Johansson, O; Virtanen, M; Hilliges, M; Yang, Q

    1992-05-01

    Mast cells have characteristic granulae containing various glucoseaminoglycans, proteases and amines (predominantly histamine). The conventional histological methods for studying mast cells are based upon acidic ortho- and metachromatic routine stains of the glucoseaminoglycans. However, the success of these procedures is dependent upon both the fixatives and the tissues used. In this study, we wanted to find out whether an immunohistochemical procedure could overcome some of these difficulties. Normal human skin was fixed in five different types of fixative and processed for indirect immunofluorescence, using an antiserum to histamine. Only one, 4% carbodiimide in 0.1 M phosphate buffer (pH 7.4), resulted in immunostaining. The quality of the staining was good, with a high signal-to-noise ratio, and was located on the mast cells. The method made it possible to visualize small structures such as a single secreted granula, the thin cytoplasmatic extension of some cells, and a previously undescribed dendritic morphology of some of the mast cells. We therefore recommend this procedure for cellular studies of mast cells when accuracy is needed. PMID:1607297

  3. Green Approach—Multicomponent Production of Boron—Containing Hantzsch and Biginelli Esters

    Directory of Open Access Journals (Sweden)

    Joel Martínez

    2013-01-01

    Full Text Available Multicomponent reactions are excellent methods that meet the requirements of green chemistry, by reducing the number of steps, and consequently reducing purification requirements. Accordingly, in this work, 11 novel hybrid-boron-containing molecules, namely eight 1,4-dihydropyridines and three 3,4-dihydropyrimidinones, derived from formylphenylboronic acids (ortho, meta and para, were obtained using a green approach, involving H-4CR and B-3CR practices, in the presence of ethanol, which is a green solvent, and using three comparatively different modes of activation (mantle heating, yield 3%–7% in 24 h, Infrared Radiation (IR irradiation, yield 12%–17% in 12 h, and microwave irradiation, yield 18%–80%, requiring very low reaction times of 0.25–0.33 h. In addition, as a green-approach is offered, a convenient analysis, of the 12 green chemistry principles for the overall procedure was performed. Finally, since all the products are new, characterizations were carried out using common analytic procedures (1H, 11B, and 13C NMR, FAB+MS, HRMS, and IR. The accurate mass data of unexpected ions related to interactions between thioglycerol and the expected products, in the FAB+-mode, enabled unequivocal characterization of the target molecules.

  4. 岭南山竹子树皮化学成分研究%Chemical constituents of Garcinia oblongifolia Champ

    Institute of Scientific and Technical Information of China (English)

    余辅松; 邓世明; 李慧; 姚海萍; 杨先会; 刘春宇

    2013-01-01

    目的 研究藤黄属植物岭南山竹子树皮中的化学成分.方法 利用硅胶、Sephadex LH-20等色谱法对山竹子树皮中的化学成分进行分离以及根据所获单体化合物的理化性质和光谱数据(紫外、核磁共振、质谱)鉴定其结构.结果 从山竹子树皮中分离得到7个单体化合物,经鉴定分别为10-hydroxybotryococcene(1)、peplusol(2)、stigmast-4-en-3-one(3)、parvifiol(4)、1,2-benzenedicarboxylic acid bis(2-methyl heptyl)ester(5)、camboginol(6)、pedunxanthone C(7).结论 化合物1~7均为首次从该种植物中分离得到.%Objective To determine the chemical constituents in the bark of Garcinia oblongifolia Champ. Methods The constituents were isolated and purified by chromatography. Their structures were identified on the basis of physico-chemical proterties and spectroscopic techniques. Results 7 compouds were obtained as 10-hydroxybotryococcen (1), peplusol (2), stigmast-4-en-3-one (3), parvifiol (4), 1, 2-benzenedicarboxylic acid bis (2-methyl heptyl) ester (5), camboginol (6), and pe-dunxanthone C(7). Conclusion Compounds 1 - 7 have been isolated from this plant for the first time.

  5. Construction of Four Zn(II Coordination Polymers Used as Catalysts for the Photodegradation of Organic Dyes in Water

    Directory of Open Access Journals (Sweden)

    Lei-Lei Liu

    2016-01-01

    Full Text Available Hydrothermal reactions of Zn(OAc2·2H2O with flexible bipyridyl benzene ligand and three dicarboxylic derivatives gave rise to four new coordination polymers, [Zn7(μ4-O2(OAc10(bpmb]n (1, [Zn(5-OH-1,3-BDC(bpmb]n (2, [Zn(1,2-BDC(bpmb]n (3 and [Zn2(ADB2(bpmb]n (4 (bpmb = 1,4-bis(pyridine-3-ylmethoxybenzene, 5-OH-1,3-H2BDC = 5-hydroxy-1,3-benzenedicarboxylic acid, 1,2-H2BDC = 1,2-benzenedicarboxylic acid, H2ADB = 2,2’-azodibenzoic acid. Their structures were characterized by single-crystal X-ray diffraction, elemental analyses, IR spectra, powder X-ray diffraction (PXRD and thermogravimetric analyses (TGA. Compound 1 features a one-dimensional (1D chain structure based on the rare heptanuclear [Zn7(μ4-O(μ3-OAc2(μ2-OAc8] units. Compound 2 exhibits a novel 2D bilayer structure built from the two parallel 2D (4,4 layers. Compound 3 holds a 2D structure in which the 1,2-BDC ligands work as lockers interlocking 1D [Zn(bpmb]n chain. Compound 4 comprises a 3D framework constructed by 2D wrinkled [Zn2(ADB4]n networks and bpmb linkers with a six-connected pcu net. These results suggest that the motifs of the dicarboxylic ligands have significant effect on the final structures. These compounds exhibited relatively good photocatalytic activity towards the degradation of methylene blue (MB in aqueous solution under a Xe lamp irradiation.

  6. GC-MS analysis of phytocomponents in the ethanol extract of Polygonum chinense L.

    Directory of Open Access Journals (Sweden)

    Bagavathi Perumal Ezhilan

    2012-01-01

    Full Text Available Background: The presence of diverse secondary metabolites has been reported from species of the genus Polygonum. However, there has been not much information available on phytochemical components and biological activity in the whole plant ethanol extract of Polygonum chinense L. Objective: This study was designed to determine the phytocomponents in the whole plant ethanol extract of P. chinense. Materials and Methods: GC-MS analysis of the whole plant ethanol extract of P. chinense was performed using a Perkin-Elmer GC Clarus 500 system comprising an AOC-20i auto-sampler and a gas chromatograph interfaced to a mass spectrometer (GC-MS. Results: This investigation was carried out to determine the possible chemical components from P. chinense by GC-MS. This analysis revealed that the ethanol extract of P. chinense (whole plant contained mainly a triterpene compound-squalene (47.01%, and a plasticizer compound-1,2-benzenedicarboxylic acid, mono[2-ethylhexyl]ester (40.30%. All identified compounds were, generally, reported as having antimicrobial activity. In addition, the squalene compound also having anti-cancer, anti-oxidant, anti-tumor, chemo-preventive, pesticidal and sun-screen properties, while the plasticizer compound -1,2-benzenedicarboxylic acid, mono[2-ethylhexyl] ester reported to have anti-oxidant and anti-inflammatory properties. No activity was reported in the alcoholic compound-4-hexene-1-ol, 5-methyl-2-(1-methylethanyl-acetate-(R-. Conclusions: From the results, it is evident that P. chinense contains various bioactive compounds and is recommended as a plant of phytopharmaceutical importance.

  7. Facile synthesis of amino-functionalized titanium metal-organic frameworks and their superior visible-light photocatalytic activity for Cr(VI) reduction

    International Nuclear Information System (INIS)

    Highlights: • NH2 functionalized MIL-125(Ti) was fabricated by a facile solvothermal method. • The photocatalyst could reduce Cr(VI)–Cr(III) under visible light irradiation. • The Ti3+–Ti4+ intervalence electron transfer is important for Cr(VI) reduction. • Used NH2-MIL-125(Ti) can be recycled for the photocatalytic reduction. - Abstract: Porous metal-organic frameworks (MOFs) have been arousing a great interest in exploring the application of MOFs as photocatalyst in environment remediation. In this work, two different MOFs, Ti-benzenedicarboxylate (MIL-125(Ti)) and amino-functionalized Ti-benzenedicarboxylate (NH2-MIL-125(Ti)) were successfully synthesized via a facile solvothermal method. The MIL-125(Ti) and NH2-MIL-125(Ti) were well characterized by XRD, SEM, XPS, N2 adsorption–desorption measurements, thermogravimetric analysis and UV–vis diffuse reflectance spectra (DRS). It is revealed that the NH2-MIL-125(Ti) has well crystalline lattice, large surface area and mesoporous structure, chemical and thermal stability, and enhanced visible-light absorption up to 520 nm, which was associated with the chromophore (amino group) in the organic linker. Compared with MIL-125(Ti), NH2-MIL-125(Ti) exhibited more efficient photocatalytic activity for Cr(VI) reduction from aqueous solution under visible-light irradiation. The addition of hole scavenger, the hole scavenger concentration and the pH value of the reaction solution played important roles in the photo-catalytic reduction of Cr(VI). The presence of Ti3+–Ti4+ intervalence electron transfer was the main reason for photo-excited electrons transportation from titanium-oxo clusters to Cr(VI), facilitating the Cr(VI) reduction under the acid condition. It was demonstrated that amino-functionalized Ti(IV)-based MOFs could be promising visible-light photocatalysts for the treatment of Cr(VI)-contained wastewater

  8. Auxiliary aromatic-acid effect on the structures of a series of ZnII coordination polymers: Syntheses, crystal structures, and photoluminescence properties

    International Nuclear Information System (INIS)

    Five novel ZnII-(pyridyl)imidazole derivative coordination polymers, [Zn(L)2] (1), [Zn2(μ3-OH)L(m-BDC)] (2), [Zn2(μ3-OH)L(p-BDC)].H2O (3), [Zn2L(BTC)(H2O)].2.5H2O (4) and [Zn3.5(μ3-OH)L2(BTEC)(H2O)].H2O (5) (L=4-((2-(pyridine-2-yl)-1H-imidazol-1-yl)methyl)benzoic acid, p-H2BDC=1,4-benzenedicarboxylic acid, m-H2BDC=1,3-benzenedicarboxylic acid, H3BTC=1,3,5-benzenetricarboxylic acid, H4BTEC=1,2,4,5-benzenetetracarboxylic acid), were successfully synthesized under hydrothermal conditions through varying auxiliary aromatic-acid ligands and structurally characterized by X-ray crystallography. Compound 1 exhibits a 1D chain linked via double L bridges. Compound 2 features a well-known pcu topology with bent dicarboxylate ligand (m-H2BDC) as an auxiliary ligand, while 3 displays a bcu network with linear dicarboxylate ligand (p-H2BDC) as an auxiliary ligand. The structure of compound 4 is a novel 3D (3,5)-connected network with (4.62)(4.64.82.10.122) topology. It is interesting that compound 5 shows an intricate (3,4,8)-connected framework with (4.62)(42.63.8)(42.64)(42.618.7.86.10) topology. In addition, their infrared spectra (IR), X-ray powder diffraction (XPRD) and photoluminescent properties were also investigated in detail. - Graphical abstract: Five novel ZnII-organic architectures have been hydrothermally synthesized through varying auxiliary aromatic-acid ligands and characterized by X-ray diffraction, the photoluminescence properties of compounds 1-5 were studied.

  9. The chemistry of silica and its potential health benefits.

    Science.gov (United States)

    Martin, K R

    2007-01-01

    There is considerable interest in the effects of silica on human health in contrast to prior research which focused solely on the toxic effects of inhaled crystalline silica. However, multiple forms of silica exist in nature and silicon, a component, is the second most prevalent element after oxygen. Silica has widespread industrial applications including use as a food additive, i.e., anti-caking agent, as a means to clarify beverages, control viscosity, as an anti-foaming agent, dough modifier, and as an excipient in drugs and vitamins. Chemically, silica is an oxide of silicon, viz., silicon dioxide, and is generally colorless to white and insoluble in water. When associated with metals or minerals the family of silicates is formed. There are several water soluble forms of silica referred collectively to as silicic acid (ortho, meta, di, and tri-silicates), which are present in surface and well water in the range of 1--100 mg/L. Orthosilicic acid is the form predominantly absorbed by humans and is found in numerous tissues including bone, tendons, aorta, liver and kidney. Compelling data suggest that silica is essential for health although no RDI has been established. However, deficiency induces deformities in skull and peripheral bones, poorly formed joints, reduced contents of cartilage, collagen, and disruption of mineral balance in the femur and vertebrae. Very little toxicity data exist regarding aqueous silica consumption due, in part, to the lack of anecdotal reports of toxicity and general presumption of safety. However, a few rodent studies have been conducted, which indicate a No Observed Adverse Effects Level (NOAEL) of 50,000 ppm (mg/L) for dietary silica. In conclusion, many forms of silica exist in nature and compelling data support myriad beneficial effects of silica in water. PMID:17435951

  10. Volatile Constituent of Black Pearl Wax Apple Fruit at Different Developmental Stages%黑珍珠莲雾果实不同发育阶段挥发物成分分析

    Institute of Scientific and Technical Information of China (English)

    阮赞誉; 金菊; 范骁凌

    2013-01-01

    利用固相微萃取法(SPME)和气质联用(GC-MS)技术对中国产黑珍珠莲雾Syzyzgium samarangense果实5个不同发育阶段的挥发物进行分析.共检测出44种物质,主要包括萜烯类、醇类、酮类和酯类,其中仅有8种物质是各阶段所共有的,它们是(-)-α-(玷)王巴烯、β-石竹烯、á-芹子烯、à-芹子烯、α-依兰油烯、6-杜松烯、2,4 ′,5-三甲基二苯基甲烷、邻苯二甲酸二异丁酯.酮类主要包括莰酮和反式-β-紫罗酮-5,6-环氧化物,酯类化合物包括邻苯二甲酸二异丁酯和乙酸异丁酯.在果实的不同发育阶段,挥发物成分与含量差异很大,萜烯类的相对含量随着果实的成熟而减少,莰酮和邻苯二甲酸二异丁酯的含量随着果实的成熟逐渐升高,反式-β-紫罗酮-5,6-环氧化物与乙酸异丁酯仅在成熟期才大量出现.%The volatile constituents from five different developmental stages of black pearl wax apple fruit ( Syzyzgium samarangense) growing in China were analysed by solid phase microextraction (SPME) and gas chromatography-mass spectrometry (GC-MS). Forty-four compounds were identified in wax apple, a-mong which volatiles, terpenoids, alcohols, ketones and esters were the major components, among which eight compounds were observed at all five developmental stages, i. e. , (-)-α-copaene, β-caryophyllene, a-selinene, a-selinene, α-muurolene, δ-cadinene, 2,4', 5-trimethyl diphenylmethane, 1, 2-benzenedi-carboxylic acid bis[2-methylpropyl] ester. Ketones of wax apple fruit included camphor and trans-beta-ionone-5 , 6-epoxide, esters components comprised 1, 2-benzenedicarboxylic acid bis [ 2-methylpropyl ] ester and acetic acid, 2-methylpropyl ester. The volatile compositions from five developmental stages of the fruit were quite different. The relative contents of terpenoids gradually decreased, and those of camphor and 1,2-benzenedicarboxylic acid bis [2-methylpropyl] ester increased along with the fruit ripening

  11. Facile synthesis of amino-functionalized titanium metal-organic frameworks and their superior visible-light photocatalytic activity for Cr(VI) reduction

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Hou [College of Environmental Science and Engineering, Hunan University, Changsha 410082 (China); Key Laboratory of Environment Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082 (China); Yuan, Xingzhong, E-mail: yxz@hnu.edu.cn [College of Environmental Science and Engineering, Hunan University, Changsha 410082 (China); Key Laboratory of Environment Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082 (China); Wu, Yan [College of Environment and Energy, South China University of Technology, Guangzhou 510006 (China); Zeng, Guangming [College of Environmental Science and Engineering, Hunan University, Changsha 410082 (China); Key Laboratory of Environment Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082 (China); Chen, Xiaohong [School of Business, Central South University, Changsha 410083 (China); Leng, Lijian; Wu, Zhibin; Jiang, Longbo [College of Environmental Science and Engineering, Hunan University, Changsha 410082 (China); Key Laboratory of Environment Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082 (China); Li, Hui [Institute of Bio-energy, Hunan Academy of Forestry, Changsha 410004 (China)

    2015-04-09

    Highlights: • NH{sub 2} functionalized MIL-125(Ti) was fabricated by a facile solvothermal method. • The photocatalyst could reduce Cr(VI)–Cr(III) under visible light irradiation. • The Ti{sup 3+}–Ti{sup 4+} intervalence electron transfer is important for Cr(VI) reduction. • Used NH{sub 2}-MIL-125(Ti) can be recycled for the photocatalytic reduction. - Abstract: Porous metal-organic frameworks (MOFs) have been arousing a great interest in exploring the application of MOFs as photocatalyst in environment remediation. In this work, two different MOFs, Ti-benzenedicarboxylate (MIL-125(Ti)) and amino-functionalized Ti-benzenedicarboxylate (NH{sub 2}-MIL-125(Ti)) were successfully synthesized via a facile solvothermal method. The MIL-125(Ti) and NH{sub 2}-MIL-125(Ti) were well characterized by XRD, SEM, XPS, N{sub 2} adsorption–desorption measurements, thermogravimetric analysis and UV–vis diffuse reflectance spectra (DRS). It is revealed that the NH{sub 2}-MIL-125(Ti) has well crystalline lattice, large surface area and mesoporous structure, chemical and thermal stability, and enhanced visible-light absorption up to 520 nm, which was associated with the chromophore (amino group) in the organic linker. Compared with MIL-125(Ti), NH{sub 2}-MIL-125(Ti) exhibited more efficient photocatalytic activity for Cr(VI) reduction from aqueous solution under visible-light irradiation. The addition of hole scavenger, the hole scavenger concentration and the pH value of the reaction solution played important roles in the photo-catalytic reduction of Cr(VI). The presence of Ti{sup 3+}–Ti{sup 4+} intervalence electron transfer was the main reason for photo-excited electrons transportation from titanium-oxo clusters to Cr(VI), facilitating the Cr(VI) reduction under the acid condition. It was demonstrated that amino-functionalized Ti(IV)-based MOFs could be promising visible-light photocatalysts for the treatment of Cr(VI)-contained wastewater.

  12. COMPARISON OF BIOACTIVE ANTHOCYANIN COMPONENTS FROM BEGONIA MALABARICA LAM. AND BEGONIA REX-CULTORUM ?BABY RAINBOW? L.H.BAILEY BY GC-MS ANALYSIS

    Directory of Open Access Journals (Sweden)

    Aswathy JM

    2015-07-01

    Full Text Available Anthocyanins, derivatives of 2-phenylbenzopyryliumare are water-soluble natural pigments. Owing to extensive scientific research they have become not only the colouring food products but also therapeutic sources of bioactive compounds and continue to play role in the maintenance of human health. Begonia malabarica Lam. and Begonia rex-cultorum ‘baby rainbow’ L.H. Bailey are common ornamentals with varied leaf colour combinations were analyzed by Gas Chromatography-Mass Spectrometry to determine the bioactive constituents present in the methanolic extracts of the leaves. Powdered leaf samples were subjected to Soxhlet extraction method with methanol and the extract was fractioned by GC-MS. Totally, 7 different compounds each from B. malabarica [phenol, 2,4-bis (1,1-dimethylethyl, hexadecanoic acid, methyl ester, 9,12-octadecadienoic acid (Z,Z, methyl ester, 9,12,15- octadecatrienoic acid, methyl ester, (Z,Z,Z, 1,2-benzenedicarboxylic acid, diisooctyl ester, Spiro[furan-2(5H,2'(1'H- naphtho[2,1-b]furan]-5-one, 3'a,4',5',5'a,6',7',8',9',9'a,9'b-decahydro-3,3'a,6',6',9'a-pentamethyl and androst-1-en-3- one, 4,4-dimethyl-, (5.alpha.] and B. rex ‘baby rainbow’ [diethyl Phthalate, 1-(3,6,6-trimethyl-1,6,7,7atetrahydrocyclopenta[ c]pyran-1-yl ethanone, hexadecanoic acid, methyl ester, 7,10-octadecadienoic acid, methyl ester, 9,12,15-octadecatrienoic acid, methyl ester, (Z,Z,Z, 5,9 methanobenzocycloocten-1(2H-one,3,4,5,6,7,8,9,10- octahydro-5,10-dihydroxy-3,3,7,7,9-pentamethyl and 1,2-benzenedicarboxylic acid, diisooctyl ester] were identified. All the compounds identified were medicinally proven for the treatment of various human ailments. Further studies are warranted to purify the lead molecules and to evaluate their biological properties including toxicological aspects for the development of novel drugs.

  13. Accessing postsynthetic modification in a series of metal-organic frameworks and the influence of framework topology on reactivity.

    Science.gov (United States)

    Wang, Zhenqiang; Tanabe, Kristine K; Cohen, Seth M

    2009-01-01

    2-Amino-1,4-benzenedicarboxylic acid (NH(2)-BDC) has been found to be a compatible building block for the construction of two new metal-organic frameworks (MOFs) that have structures isoreticular to reported MOFs that use 1,4-benzenedicarboxylic acid (BDC) as a building block. DMOF-1-NH(2) (DABCO MOF-1-NH(2)) is a derivative of a previously studied MOF that contains two-dimensional square grids based on NH(2)-BDC and zinc(II) paddle-wheel units; the grid layers are connected by DABCO (1,4-diazabicyclo[2.2.2]octane) molecules that coordinate in the axial positions of the paddlewheel secondary-building units (SBUs). UMCM-1-NH(2) is an NH(2)-BDC derivative of UMCM-1 (University of Michigan Crystalline Material-1), a highly porous MOF reported by Matzger et al., and consists of both NH(2)-BDC and BTB (BTB = 4,4',4''-benzene-1,3,5-triyl-tribenzoate) linkers with Zn(4)O SBUs. The structure of UMCM-1-NH(2) was confirmed by single-crystal X-ray diffraction. By using NH(2)-BDC to generate these MOFs, the pendant amino groups can serve as a chemical handle that can be manipulated via postsynthetic modification with alkyl anhydrides. Reactions of each MOF and different anhydrides have been performed to compare the extent of conversion, thermal and structural stability, and Brunauer-Emmett-Teller surface areas afforded by the resulting materials. Under comparable reaction conditions, (1)H NMR of digested samples show that UMCM-1-NH(2) has conversions comparable to that of IRMOF-3, while DMOF-1-NH(2) only shows high conversions with smaller anhydrides. Under specific reaction conditions, higher conversions were obtained with complete retention of crystallinity, as verified by single-crystal X-ray diffraction experiments. The results presented here demonstrate three important findings: (a) NH(2)-BDC can be used as a surrogate for BDC in a number of MOFs thereby providing a handle for postsynthetic modification, (b) postsynthetic modification is a general strategy to

  14. Anti-candidal activity of Astragalus verus in the in vitro and in vivo guinea pig models of cutaneous and systemic candidiasis

    Directory of Open Access Journals (Sweden)

    Ali Mikaeili

    2012-10-01

    Full Text Available This study was design to evaluate the anti-candidal activity of Astragalus verus Olivier, Fabaceae (Av. The GC/MS analysis of essential oils of Av showed that aqueous extract contains thymol while hexadecanoic acid, 1,2-benzenedicarboxylic acid, diisooctyl ester and phytol were found as major components of methanol and acetone extracts. The aqueous extract showed anti-candidal activity in the concentration 320 mg/mL using disc diffusion method and its minimum inhibitory concentration (MIC was 160 mg/mL. To induce cutaneous candidiasis, the dorsum of immunocompromised guinea pigs was infected with Candida albicans and animals were divided into five groups (n=5 for each: NC, received a vehicle; PC, received topical ketoconazole 2% and three other groups which received topical 10, 20 and 40% aqueous extract of Av. On ninth day postinfection, skins were cultured and colony forming unite per gram (CFU/g skin was recorded. Systemic candidiasis was obtained by intravenous inoculation of C. albicans, 4000 CFU/g body weight. Here, animals have been divided into five groups like cutaneous candidiasis but their medications have been delivered in drinking water for ten days before induction of infection. On second day postinfection, all internal tissues were taken for determining CFU/g tissue. The aqueous extract (40% prevented heavy burden of C. albicans in tissues and skin in oral and topical application, respectively. The results indicate that Av represents a potential source of anti-candidal drug.

  15. Pyrolysis of Polytrimethylene Terephthalate (PTT) Fiber by Pyrolysis Gas Chromatography-Mass Spectroscopy

    Institute of Scientific and Technical Information of China (English)

    QIAN He-sheng

    2007-01-01

    Pyrolysis of polytrimethylene terephthalate (PTT) fiber has been investigated by pyrolysis gas chromatography-mass spectroscopy in the temperature range from 400℃ to 750℃ in order to observe the possible effect of the temperature on its composition of pyrolysates. At 400℃, pyrolysis of molecular chain could occur, only 13 pyrolysates could be identified. The trimethylene moieties bound to the macromolecular core by ester bonds are cleaved at around 400℃. At 550℃ -750℃, pyrolysis of molecular chain could completely take place, 46 pyrolysates could be found. As the temperature increases, the compositions of pyrolysate are distinctly increased. Several compounds, especially benzoic acid, monopropenyl-p-phthalate, 2 - propenyl benzoate, di - 2 - propenyl ester, 1,4 -benzenedicarboxylic acid, benzene, 1, 5 - hexadiene, biphenyl and 1, 3 - propanediol dibenzoate could be formed. The thermal degradation mechanism, which is determined by structure and amount of the thermal decomposition products, are described. During pyrolysis of polytrimethylene terephthalate, polymeric chain scissions take place a peeling reaction as a successive removal of the dimer units from the polymeric chain. The chain scissions are followed by the elimination reaction, linkage action and secondary reactions, which bring about a variety fragment.

  16. Conversion and degradation of crude oil by Bacillus SP3

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The objective of this study is to demonstrate the basic characteristics of Bacillus SP3 and evaluate its effect on different crude oils. Strain SP3 is a motile, gram-positive, spore-producing rod that was isolated from a reservoir of the Shengli oil field in East China. The cells of strain SP3 grew at high temperatures up to 58℃ at the pH range of 5.5-8.5. Strain SP3 grew facultatively and could use different organic substrates, and produce some metabolites such as 4-hydroxy-4-methyl-2-pentanone, methyl-2-nitrogen benzene and 1, 2-benzenedicarboxylic acid bis ester. Laboratory studies have demonstrated that the strain converted and degraded different components and changed the physical and chemical properties of crude oils. Strain SP3 degraded crude oil and the growth of bacteria on crude oil resulted in loss of aromatic hydrocarbons, resins and asphaltenes. The bioconversion of crude oils would lead to an enrichment in lighter hydrocarbons and an overall redistribution of saturate hydrocarbons. The interactions of microorganisms with crude oils are variable, depending on the microbial species and the chemical compositions of crude oils.

  17. Occurrence of an Octa-nuclear Motif of Uranyl Isophthalate with Cation-Cation Interactions through Edge-Sharing Connection Mode

    International Nuclear Information System (INIS)

    An uranyl isophthalate has been hydrothermally synthesized at 200 degrees C for 24 h, from a mixture of uranyl nitrate, isophthalic acid, and hydrazine in water. It was characterized by single-crystal analysis [triclinic, P1-bar a = 7.3934(3) Angstrom, b = 13.3296(5) Angstrom, = 15.4432(5) Angstrom, α = 111.865(2)degrees, β = 90.637(2)degrees, γ 104.867(2)degrees, V = 1355.49(9) Angstrom3] and different spectroscopic techniques (Raman, IR-ATR, UV visible), The 3D structure of the phase (UO2)8O2(OH)4(H2O)4(1,3-bdc)4.4H2O (1,3-bdc = 1,3-benzenedicarboxylate) reveals octa-nuclear units based on the association of 7-fold coordinated uranyl cations (pentagonal bipyramid) involving a rare case of cation cation interaction together with edge-sharing polyhedral connection mode. UV visible absorption spectroscopy confirmed that uranium was only involved in the structure as uranyl forms (excluding the assigning four uranyl presence of tetravalent or pentavalent uranium). Additionally, μ-Raman and IR-ATR experiments allowed contributions to the four types of uranyl entities in the structure, in agreement with the XRD analysis. (authors)

  18. Synthesis and structure determination of new open-framework chromium carboxylate MIL-105 or CrIII(OH).{O2C-C6(CH3)4-CO2}.nH2O

    International Nuclear Information System (INIS)

    Two new three-dimensional chromium(III) dicarboxylate, MIL-105 or CrIII(OH).{O2C-C6(CH3)4-CO2}.nH2O, have been obtained under hydrothermal conditions, and their structures solved using X-ray powder diffraction data. Both solids are structural analogs of the known Cr benzenedicarboxylate compound (MIL-53). Both contain trans corner-sharing CrO4(OH)2 octahedral chains connected by tetramethylterephthalate di-anions. Each chain is linked by the ligands to four other chains to form a three-dimensional framework with an array of 1D pores channels. The pores of the high temperature form of the solid, MIL-105ht, are empty. However, MIL-105ht re-hydrates at room temperature to finally give MIL-105lt with pores channels filled with free water molecules (lt: low temperature form; ht: high temperature form). The thermal behaviour of the two solids has been investigated using TGA. Crystal data for MIL-105ht: monoclinic space group C2/c with a = 19.653(1) A, b = 9.984(1) A, c = 6.970(1) A, β = 110.67(1)o and Z = 4. Crystal data for MIL-105lt: orthorhombic space group Pnam with a = 17.892(1) A, b = 11.165(1) A, c = 6.916(1) A and Z = 4

  19. Biodegradation of heavy oils by halophilic bacterium

    Institute of Scientific and Technical Information of China (English)

    Ruixia Hao; Anhuai Lu

    2009-01-01

    A halophilic bacterial strain TM-1 was isolated from the reservoir of the Shengli oil field in East China. Strain TM-1, which was found to be able to degrade crude oils, is a gram-positive non-motile bacterium with a coccus shape that can grow at temperatures of up to 58 ℃ and in 18% NaCl solution. Depending on the culture conditions, the organism may occur in tetrads. In addition, strain TM-1 pro-duced acid from glucose without gas formation and was catalase-negative. Furthermore, strain TM-I was found to be a facultative aer-obe capable of growth under anaerobic conditions. Moreover, it produced butylated hydroxytoluene, 1,2-benzenedicarboxylic acid-bis ester and dibutyl phthalate and could use different organic substrates. Laboratory studies indicated that strain TM-1 affected different heavy oils by degrading various components and by changing the chemical properties of the oils. In addition, growth of the bacterium in heavy oils resulted in the loss of aromatic hydrocarbons, resins and asphaltenes, and enrichment with light hydrocarbons and an overall redistribution of these hydrocarbons.

  20. Detection of intermediates in the TiO2-assisted photodegradation of Rhodamine B under visible light irradiation

    Institute of Scientific and Technical Information of China (English)

    LI Jing-yi; MA Wan-hong; LEI Peng-xiang; ZHAO Jin-cai

    2007-01-01

    The photocatalytic degradation of dye Rhodamine B (RhB) in the presence of TiO2 nanostripe or P25 under visible light irradiation was investigated. The degradation intermediates were identified using Infrared spectra (IR spectra), 1H nuclear magnetic resonance (1HNMR) spectra, and gas chromatography-mass spectroscopy (GC-MS). The IR and the 1HNMR results showed that the large conjugated chromophore structure of RhB was efficiently destroyed under visible light irradiation in both the photocatalytic systems (TiO2 nanostripe or P25 and Rhodamine B systems). GC-MS results showed that the main identified intermediates are ethanediotic acid, 1,2-benzenedicarboxylic acid, 4-hydroxy benzoic acid and benzoic acid, which are almost the same in the TiO2 nanostripes and P25 systems. This work provides a good insight into the reaction pathway(s) for the TiO2-assisted photocatalytic degradation of dye pollutants under visible light irradiation.

  1. Remarkable adsorptive removal of nitrogen-containing compounds from a model fuel by a graphene oxide/MIL-101 composite through a combined effect of improved porosity and hydrogen bonding.

    Science.gov (United States)

    Ahmed, Imteaz; Jhung, Sung Hwa

    2016-08-15

    A composite was prepared by combining a highly porous metal-organic framework (MOF), MIL-101 (Cr-benzenedicarboxylate), and graphene oxide (GnO). The porosity of the composite increased appreciably by the addition of GnO up to a specific amount in the MOF, though further increases in the quantity of GnO was detrimental to porosity. The improved porosity of the GnO/MIL-101 composite was utilized for adsorptive denitrogenation (ADN) of a model fuel where indole (IND) and quinoline (QUI) were used as nitrogen-containing compounds (NCCs). It was found that both IND and QUI showed improved adsorption on the composite compared with pristine MIL-101 or GnO due to the improved porosity of the composite. Interestingly, the improvement in adsorption of IND was much higher than the quantity estimated for the porosity. Importantly, GnO/MIL-101 showed the highest adsorption capacities for NCCs. Irrespective of the studied solvents and co-presence of IND and QUI, the composite adsorbent performed ADN most effectively. This remarkable improvement is explained by the additional mechanism of hydrogen bonding between the surface functional groups of GnO and the hydrogen attached to the nitrogen atom of IND. This hydrogen bonding mechanism is also supported by the results of the adsorption of pyrrole and methylpyrrole. On the other hand, QUI does not show hydrogen-bonding capability, and therefore, its enhanced adsorption originates from only the increased porosity of the adsorbents. PMID:27152881

  2. Phthalic Acid Chemical Probes Synthesized for Protein-Protein Interaction Analysis

    Directory of Open Access Journals (Sweden)

    Chin-Jen Wu

    2013-06-01

    Full Text Available Plasticizers are additives that are used to increase the flexibility of plastic during manufacturing. However, in injection molding processes, plasticizers cannot be generated with monomers because they can peel off from the plastics into the surrounding environment, water, or food, or become attached to skin. Among the various plasticizers that are used, 1,2-benzenedicarboxylic acid (phthalic acid is a typical precursor to generate phthalates. In addition, phthalic acid is a metabolite of diethylhexyl phthalate (DEHP. According to Gene_Ontology gene/protein database, phthalates can cause genital diseases, cardiotoxicity, hepatotoxicity, nephrotoxicity, etc. In this study, a silanized linker (3-aminopropyl triethoxyslane, APTES was deposited on silicon dioxides (SiO2 particles and phthalate chemical probes were manufactured from phthalic acid and APTES–SiO2. These probes could be used for detecting proteins that targeted phthalic acid and for protein-protein interactions. The phthalic acid chemical probes we produced were incubated with epithelioid cell lysates of normal rat kidney (NRK-52E cells to detect the interactions between phthalic acid and NRK-52E extracted proteins. These chemical probes interacted with a number of chaperones such as protein disulfide-isomerase A6, heat shock proteins, and Serpin H1. Ingenuity Pathways Analysis (IPA software showed that these chemical probes were a practical technique for protein-protein interaction analysis.

  3. Metal-organic frameworks based on rigid ligands as separator membranes in supercapacitor.

    Science.gov (United States)

    Meng, Jiang-Ping; Gong, Yun; Lin, Qiang; Zhang, Miao-Miao; Zhang, Pan; Shi, Hui-Fang; Lin, Jian-Hua

    2015-03-28

    Two thermally stable MOFs formulated as CoL(1,4-bdc)·2DMF (L = 3,5-bis(5-(pyridin-4-yl)-4H-1,2,4-triazol-3-yl)pyridine), 1,4-H2bdc = 1,4-benzenedicarboxylic acid) (1) and CdL(4,4'-bpc)·3DMF (4,4'-H2bpc = 4,4'-biphenyldicarboxylic acid) (2) have been solvothermally synthesized and exhibit a similar uninodal 6-connected 3D architecture with {4(12)·6(3)}-pcu topology. MOF1 shows a non-interpenetrated network with larger channel, whereas MOF 2 exhibits a 3-fold interpenetrating framework with smaller pore size. When the two MOFs are used as separator membranes in a supercapacitor, the equivalent series resistance (Res) is larger than the Res in the blank supercapacitor, and the smaller the current density, the more the Res. After being charged and discharged at the low current density, the supercapacitor with MOF 1 as separator membrane (denoted as 1a) possesses a much larger specific capacitance (SC) than the blank supercapacitor, and the amorphous separator membrane 1a shows a more porous morphology than the original MOF membrane 1. PMID:25689346

  4. Ultra-trace graphene oxide in a water environment triggers Parkinson's disease-like symptoms and metabolic disturbance in zebrafish larvae.

    Science.gov (United States)

    Ren, Chaoxiu; Hu, Xiangang; Li, Xueyan; Zhou, Qixing

    2016-07-01

    Over the past decade, the safety of nanomaterials has attracted attention due to their rapid development. The relevant health threat of these materials remains largely unknown, particularly at environmentally or biologically relevant ultra-trace concentrations. To address this, we first found that graphene oxide (GO, a carbon nanomaterial that receives extensive attention across various disciplines) at concentrations of 0.01 μg/L-1 μg/L induced Parkinson's disease-like symptoms in zebrafish larvae. In this model, zebrafish showed a loss of more than 90% of dopamine neurons, a 69-522% increase in Lewy bodies (α-synuclein and ubiquitin) and significantly disturbed locomotive activity. Moreover, it was also shown that GO was able to translocate from the water environment to the brain and localize to the nucleus of the diencephalon, thereby inducing structural and morphological damage in the mitochondria. Cell apoptosis and senescence were triggered via oxidative stress, as shown by the upregulation of caspase 8 and β-galactosidase. Using metabolomics, we found that the upregulation of amino acid and some fatty acids (e.g. dodecanoic acid, hexadecanoic acid, octadecenoic acid, nonanoic acid, arachidonic acid, eicosanoic acid, propanoic acid and benzenedicarboxylic acid) metabolism and the downregulation of some other fatty acids (e.g. butanoic acid, phthalic acid and docosenoic acid) are linked to these Parkinson's disease-like symptoms. These findings broaden our understanding of nanomaterial safety at ultra-trace concentrations. PMID:27085073

  5. Synthesis, Structure and Photoluminescence of One Zinc-based Metal-metallosalen Framework

    Institute of Scientific and Technical Information of China (English)

    ZHU Cheng-Feng; BAN Feng-Jun; SHENG En-Hong; ZHENG Sai-Jing; LIU Bai-Zhan; CUI Yong

    2013-01-01

    Dicarboxyl-functionalized salen ligand 1,2-phenylendiamine-N,N'-bis(3-tert-butyl-5-(carboxyl)-salicylide-ene (H4L) was synthesized in good yield from 3-tert-butyl-5-formyl-4-hydroxybenzoic acid and used to construct a 2D zinc complex,[(ZnL)Zn3/2(BDC)1/2(DMSO)2]·3DMSO(1,BDC =1,4-benzenedicarboxylate),under mild reaction conditions.1 was characterized by IR,microanalysis,TGA and single-crystal X-ray crystallography.It crystallizes in triclinic space group Pī with a =11.3860(4),b =13.2636(5),c =17.5503(7) (A),α=92.2240(10),β =94.5070(10),γ =96.0580(10)°,V=2624.52(17) (A)3,Z=2,Mr =1143.62,Dc =1.448 g/cm3,F(000) =1186,μ =1.395mm-1,GOOF =0.993,the final R =0.0380 and wR =0.1280 for 21752 observed reflections with I >2σ(I).The 2D coordination polymer 1 is further assembled into a 3D supramolecular network structure via π…π interactions between the aromatic rings of the ligands in adjacent layers.Thermal gravimetric analysis demonstrates that 1 is a thermally robust structure with network decomposition temperatures of 420 ℃ and it also exhibits strong photoluminescence in the visible region.

  6. Hydrogen adsorption in metal-organic frameworks

    International Nuclear Information System (INIS)

    Metal-Organic Frameworks (MOFs) have recently received considerable attention because of their high specific micropore volume and the ability to store gas molecules exceeding the storage capacity of traditional adsorbents. A variety of differences in the MOFs structures makes it difficult to analyze the influence of different factors on hydrogen uptake capabilities in MOFs. We have investigated the influence of the minor structural changes of the MOFs on their hydrogen storage capacity. The influence of the incorporated metal was shown for following isostructural compounds: Cu3(BTC)2 (BTC=1,3,5-benzenetricarboxylate) and Mo3(BTC)2; Zn2(BDC)2DABCO and Co2(BDC)2DABCO (BDC=1,4-benzenedicarboxylate, DABCO=1,4-diazabicyclo[2.2.2]octane). Our research interest is directed also towards the discovery of new MOFs, as well as adjusting the pore dimensions of MOFs, using different building blocks, solvent and solvent mixtures, in order to improve gas uptake and adsorption properties. Magnesium-based MOFs were found with the same network topology, very small pore size and selective adsorption behaviour. They show a guest-induced reversible structure transformation due to the flexibility of the Mg3-cluster and the organic linkers. This effect could be used for fitting the pore sizes and for the increase of gas sorption capability in Mg contained MOFs after all. The hydrogen adsorption was also studied in several Al-based IRMOFs

  7. Two anionic metal-organic frameworks with tunable luminescent properties induced by cations

    Science.gov (United States)

    Chen, Shu-Mei; Chen, Yan-Fei; Liu, Liyang; Wen, Tian; Zhang, Hua-Bin; Zhang, Jian

    2016-03-01

    Two three-dimensional (3-D) MOFs, [(C2H5)4N)]3[H3O]2[Cd6Br(H2-DHBDC)8(DMF)4] (1; H4-DHBDC=2,5-dihydroxy-1,4-benzenedicarboxylic acid, DMF=N,N-dimethylformamide) and [(CH3)2NH2]2[Cd3(H2-DHBDC)4(DMF)2]·2DMF(2), are prepared from the self-assembly reactions between Cd(CH3COO)2 and H4-DHBDC, respectively. Both anionic frameworks consist of linear trinuclear Cd units (e.g., 1: [Cd3BrO2(CO2)7] and [Cd3O2(CO2)8]; 2: [Cd3O2(CO2)8]) linked by the H2-DHBDC ligands. The photoluminescent properties of compound 1 are tunable through cation-exchange with different metal ions. The results demonstrated an effective ion-exchange approach toward the functional modification of MOF materials.

  8. Nanometrization of Lanthanide-Based Coordination Polymers.

    Science.gov (United States)

    Neaime, Chrystelle; Daiguebonne, Carole; Calvez, Guillaume; Freslon, Stéphane; Bernot, Kevin; Grasset, Fabien; Cordier, Stéphane; Guillou, Olivier

    2015-11-23

    Heteronuclear lanthanide-based coordination polymers are microcrystalline powders, the luminescence properties of which can be precisely tuned by judicious choice of the rare-earth ions. In this study, we demonstrate that such materials can also be obtained as stable solutions of nanoparticles in non-toxic polyols. Bulk powders of the formula [Ln2-2x Ln'2x (bdc)3 ⋅4 H2 O]∞ (where H2 bdc denotes 1,4-benzene-dicarboxylic acid, 0≤x≤1, and Ln and Ln' denote lanthanide ions of the series La to Tm plus Y) afford nanoparticles that have been characterized by dynamic light-scattering (DLS) and transmission electron microscopy (TEM) measurements. Their luminescence properties are similar to those of the bulk materials. Stabilities versus time and versus dilution with another solvent have been studied. This study has revealed that it is possible to tune the size of the nanoparticles. This process offers a reliable means of synthesizing suspensions of nanoparticles with tunable luminescence properties and tunable size distributions in a green solvent (glycerol). The process is also extendable to other coordination polymers and other solvents (ethylene glycol, for example). It constitutes a new route for the facile solubilization of lanthanide-based coordination polymers. PMID:26471940

  9. Confirming anthropogenic influences on the major organic and inorganic constituents of rainwater in an urban area

    Directory of Open Access Journals (Sweden)

    K. Chon

    2015-06-01

    Full Text Available The chemical composition and organic compounds of rainwater were investigated from June to December 2012 at Gwangju in Korea. The volume weighted mean of pH ranged from 3.83 to 8.90 with an average of 5.78. 50 % of rainwater samples had pH values below 5.6. The volume-weighted mean concentration (VWMC of major ions followed the order: Cl− > SO42− > NH4+ > Na+ > NO3− > Ca2+ > Mg2+ > K+. The VWMC of trace metals decreased in the order as follows Zn > Al > Fe > Mn > Pb > Cu > Ni > Cd > Cr. The VWMCs of major ions and trace metals were higher in winter than in summer. The high enrichment factors indicate that Zn, Pb, Cu, and Cd originated predominantly from anthropogenic sources. Factor analysis (principal component analysis indicates the influence of anthropogenic pollutants, sea salt, and crustal materials on the chemical compositions of rainwater. Benzoic acids, 1H-Isoindole-1,3(2H-dione, phthalic anhydride, benzene, acetic acids, 1,2-benzenedicarboxylic acids, benzonitrile, acetaldehyde, and acetamide were the most prominent pyrolysis fragments for rainwater organic compounds identified by pyrolysis gas chromatography/mass spectrometry (Py-GC/MS. The results indicate that anthropogenic sources are the most important factors affecting the organic composition of rainwater in urban area.

  10. Occurrence and spatial distribution of microplastics in sediments from Norderney

    International Nuclear Information System (INIS)

    The spatial distribution of small potential microplastics (SPM) (1 mm) was also examined. Small microparticles were extracted from 36 one kg sediment samples and analysed by visual microscopic inspection and partly by thermal desorption pyrolysis gas chromatography/mass spectrometry. The smallest particle size that could be analysed with this method was estimated to be 100 μm. The mean number of SPM at the three sampling sites (n = 12) was 1.7, 1.3 and 2.3 particles per kg dry sediment, respectively. SPM were identified as polypropylene, polyethylene, polyethylene terephthalate, polyvinylchloride, polystyrene and polyamide. The organic plastic additives found were benzophenone, 1,2-benzenedicarboxylic acid, dimethyl phthalate, diethylhexyl phthalate, dibutyl phthalate, diethyl phthalate, phenol and 2,4-di-tert-butylphenol. Particles were distributed rather homogenously and the occurrence of SPM did not correlate with that of VPD. -- Highlights: • The small-scale variability of small potential microplastics (<1 mm) occurrence in beach sediments was studied. • Within 500 m, small potential microplastics (<1 mm) were distributed rather homogeneously in investigated beach sediments. • The occurrence of small potential microplastics (<1 mm) did not correlate with that of visible plastic debris. • Procedural contamination of sediments by fibres (blank) constitutes an analytical problem. • These findings must be considered when setting up standardized monitoring protocols. -- On a small scale within 500 m, small microplastics are distributed rather homogeneously in sediments from the North Sea island of Norderney

  11. Two 2-D 36 tessellated metal-organic frameworks constructed from trimetallic clusters and dicarboxylate ditopic links

    International Nuclear Information System (INIS)

    Two metal-organic framework compounds, [Zn3(1,4-BDC)3(Py)2].2(1,4-dioxane) (MOF-CJ6) and [Cd3(bpdc)3(H2O)2] (MOF-CJ7), have been solvothermally synthesized and characterized by single crystal X-ray diffraction, X-ray powder diffraction, ICP, IR and photoluminescence spectroscopy analyses, respectively. MOF-CJ6 crystallizes in monoclinic, space group P2(1)/n (no. 14) with a = 14.6886(14) A, b = 9.6194(6) A, c = 15.9161(16) A and β = 105.687(6)o. Its framework can be described as a 2-D 36 tessellated net based on the assembly of trimeric Zn3(CO2)6 clusters and 1,4-benzenedicarboxylates ditopic links. The 2-D nets can be further linked into a novel 3-D supramolecular hexagonal lattice (hex) network through π-π packing interaction. MOF-CJ7 crystallizes in trigonal, space group R-3 (no. 148) with a = 14.1129(8) A, b = 14.1129(8) A, c = 20.1168(13) A and γ = 120o. MOF-CJ7 exhibits analogous framework topology with that of MOF-CJ6, consisting of trimeric Cd3(CO2)6 clusters and 4,4'-biphenyldicarboxylate links

  12. Thermodynamics of hydrogen adsorption in MOF-177 at low temperatures: measurements and modelling

    International Nuclear Information System (INIS)

    Hydrogen adsorption measurements and modelling for the Zn-based microporous metal-organic framework (MOF) Zn4O(1,3,5-benzenetribenzoate)2, MOF-177, were performed over the 50-77 K and 0-40 bar ranges. The maximum excess adsorption measured under these conditions varies over about 105-70 mg g-1. An analysis of the isotherms near saturation shows that hydrogen is ultimately adsorbed in an incompressible phase whose density is comparable to that of the bulk liquid. These liquid state properties observed under supercritical conditions reveal a remarkable effect of nanoscale confinement. The entire set of adsorption isotherms can be well described using a micropore filling model. The latter is used, in particular, to determine the absolute amounts adsorbed and the adsorption enthalpy. When expressed in terms of absolute adsorption, the isotherms show considerable hydrogen storage capacities, reaching up to 125 mg g-1 at 50 K and 25 bar. The adsorption enthalpies are calculated as a function of fractional filling and range from 3 to 5 kJ mol-1 in magnitude, in accordance with physisorption. These results are discussed with respect to a similar analysis performed on another Zn-based MOF, Zn4O(1,4-benzenedicarboxylate)3, IRMOF-1, presented recently. It is found that both materials adsorb hydrogen by similar mechanisms.

  13. Porous carbon as electrode material in direct ethanol fuel cells (DEFCs) synthesized by the direct carbonization of MOF-5

    KAUST Repository

    Khan, Inayatali

    2014-01-12

    Porous carbon (PC-900) was prepared by direct carbonization of porous metal-organic framework (MOF)-5 (Zn4O(bdc)3, bdc=1,4-benzenedicarboxylate) at 900 °C. The carbon material was deposited with PtM (M=Fe, Ni, Co, and Cu (20 %) metal loading) nanoparticles using the polyol reduction method, and catalysts PtM/PC-900 were designed for direct ethanol fuel cells (DEFCs). However, herein, we are reporting PtFe/PC-900 catalyst combination which has exhibited superior performance among other options. This catalyst was characterized by powder XRD, high-resolution transmission electron microscopy (HRTEM), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), and selected area electron diffraction (SAED) technique. The electrocatalytic capability of the catalyst for ethanol electrooxidation was investigated using cyclic voltammetry and direct ethanol single cell testing. The results were compared with those of PtFe and Pt supported on Vulcan XC72 carbon catalysts (PFe/CX-72 and Pt/XC-72) prepared via the same method. It has been observed that the catalyst PtFe/PC-900 developed in this work showed an outstanding normalized activity per gram of Pt (6.8 mA/g Pt) and superior power density (121 mW/cm2 at 90 °C) compared to commercially available carbon-supported catalysts. © Springer-Verlag Berlin Heidelberg 2014.

  14. Pore size dynamics in interpenetrated metal organic frameworks for selective sensing of aromatic compounds.

    Science.gov (United States)

    Myers, Matthew; Podolska, Anna; Heath, Charles; Baker, Murray V; Pejcic, Bobby

    2014-03-28

    The two-fold interpenetrated metal-organic framework, [Zn2(bdc)2(dpNDI)]n (bdc=1,4-benzenedicarboxylate, dpNDI=N'N'-di(4-pyridyl)-1,4,5,8-naphthalenediimide) can undergo structural re-arrangement upon adsorption of chemical species changing its pore structure. For a competitive binding process with multiple analytes of different sizes and geometries, the interpenetrated framework will adopt a conformation to maximize the overall binding interactions. In this study, we show for binary mixtures that there is a high selectivity for the larger methylated aromatic compounds, toluene and p-xylene, over the small non-methylated benzene. The dpNDI moiety within [Zn2(bdc)2(dpNDI)]n forms an exciplex with these aromatic compounds. The emission wavelength is dependent on the strength of the host-guest CT interaction allowing these compounds to be distinguished. We show that the sorption selectivity characteristics can have a significant impact on the fluorescence sensor response of [Zn2(bdc)2(dpNDI)]n towards environmentally important hydrocarbons based contaminants (i.e., BTEX, PAH). PMID:24636414

  15. First-principles study of the organometallic S =1/2 kagome compound Cu(1,3-bdc)

    Science.gov (United States)

    Liu, Zheng; Mei, Jia-Wei; Liu, Feng

    2015-10-01

    Cu(1,3-benzenedicarboxylate) [Cu(1,3-bdc)] contains structurally perfect kagome planes formed by Cu2 + ions without the presence of diamagnetic defects. This organometallic compound should serve as a precious platform to explore quantum frustrated magnetism, yet the experimental results so far are mysterious, leading to questions such as, "Is Cu(1,3-bdc) just a trivial weak ferromagnet?" Using the density functional theory, we have systematically studied the electronic and magnetic properties of Cu(1,3-bdc), putting forth a theoretical basis to clarify this novel material. We present numerical evidence of a dominating antiferromagnetic (AFM) exchange between nearest-neighbor (NN) Cu2 + as experimentally extracted from the high-temperature susceptibility data. We further show that beyond the NN AFM exchange, the additional interactions in Cu(1,3-bdc) have similar strength as those in the well-studied kagome antiferromagnet, herbertsmithite, by designing a comparative study. In the end, we discuss our understanding of the phase transition and FM signals observed under low temperature.

  16. An Adsorbate Discriminatory Gate Effect in a Flexible Porous Coordination Polymer for Selective Adsorption of CO2 over C2H2.

    Science.gov (United States)

    Foo, Maw Lin; Matsuda, Ryotaro; Hijikata, Yuh; Krishna, Rajamani; Sato, Hiroshi; Horike, Satoshi; Hori, Akihiro; Duan, Jingui; Sato, Yohei; Kubota, Yoshiki; Takata, Masaki; Kitagawa, Susumu

    2016-03-01

    The adsorptive separation of C2H2 and CO2 via porous materials is nontrivial due to the close similarities of their boiling points and kinetic diameters. In this work, we describe a new flexible porous coordination polymer (PCP) [Mn(bdc)(dpe)] (H2bdc = 1,4-benzenedicarboxylic acid, dpe = 1,2-di(4-pyridyl)ethylene) having zero-dimensional pores, which shows an adsorbate discriminatory gate effect. The compound shows gate opening type abrupt adsorption for C2H2 but not for CO2, leading to an appreciable selective adsorption of CO2 over C2H2 at near ambient temperature (273 K). The origin of this unique selectivity, as unveiled by in situ adsorption-X-ray diffraction experiments and density functional theory calculations, is due to vastly different orientations between the phenylene ring of bdc and each gas in the nanopores. The structural change by photochemical transformation of this PCP via [2 + 2] photodimerization leads to the removal of inverse CO2/C2H2 selectivity, verifying the mechanism of the guest discriminatory gate effect. PMID:26876504

  17. A family of porous lonsdaleite-e networks obtained through pillaring of decorated kagomé lattice sheets

    KAUST Repository

    Schoedel, Alexander

    2013-09-25

    A new and versatile class of metal-organic materials (MOMs) with augmented lonsdaleite-e (lon-e-a) topology is presented herein. This family of lon-e nets are built by pillaring of hexagonal two-dimensional kagomé (kag) lattices constructed from well-known [Zn2(CO2R)4] paddlewheel molecular building blocks (MBBs) connected by 1,3- benzenedicarboxylate (bdc2-) linkers. The pillars are [Cr 3(μ3-O)(RCO2)]6 trigonal prismatic primary MBBs decorated by six pyridyl moieties (tp-PMBB-1). The three-fold symmetry (D3h) of tp-PMBB-1 is complementary with the alternating orientation of the axial sites of the paddlewheel MBBs and enables triple cross-linking of the kag layers by each pillar. These MOMs represent the first examples of axial-to-axial pillared undulating kag layers, and they are readily fine-tuned because the bdc2- moieties can be varied at their 5-position without changing the overall structure. This lon-e platform possesses functionalized hexagonal channels since the kag lattices are necessarily eclipsed. The effects of the substituent at the 5-positions of the bdc 2- linkers upon gas adsorption, particularly the heats of adsorption of carbon dioxide and methane, were studied. © 2013 American Chemical Society.

  18. Synthesis, structure and electrochemical behavior of a 3D crystalline copper(II) metal-organic framework

    Science.gov (United States)

    Bai, Hong-Ye; Fan, Wei-Qiang; Liu, Chun-Bo; Shi, Wei-Dong; Yan, Yong-Sheng

    2014-05-01

    Using an flexible amide-type tripodal ligand N,N‧,N″-tris(3-pyridyl)-1,3,5-benzenetricarboxamide (L) and 1,4-benzenedicarboxylic acid (H2bdc), a three-dimensional copper(II) metal-organic framework (MOF) formulated as [Cu(bdc)(L)]n has been hydrothermally synthesized and structurally characterized by IR, elemental, X-ray single-crystal diffraction and thermal analysis. The complex crystallizes in the triclinic, space group P - 1, a = 8.891(2) Å, b = 11.760(2) Å, c = 15.348(3) Å, α = 96.73(3)°, β = 105.96(3)°, γ = 106.47(3)°, V = 1446.2(5) Å3, Mr = 666.10, Dc = 1.530 g/cm3, Z = 2, F(000) = 682, GOOF = 1.0560, μ(MoKα) = 0.817 mm-1, R = 0.0366 and wR = 0.0885. The structural analyses reveal that the title compound consists of one Cu(II) atom, two halves of bdc, and one L ligand. Each Cu(II) atom is linked by two bdc ligands and three L ligands to form a three-dimensional network. In addition, the electrochemical behavior of title compound has been studied. CCDC No. 990526.

  19. Synthesis and Characterization of Nanosized Uranyl Coordination Polymers derived from Terephthalic acid and Azoles

    Directory of Open Access Journals (Sweden)

    Maged S.Al-Fakeh

    2016-05-01

    Full Text Available The structure of the complexes [UO2(TPA(Azole(H2O].xH2O, TPA = 1,4-benzenedicarboxylic acid and azoles = 2-aminobenzothiazole, 2-aminothiazole, 2-amino-4-methylthiazole and 2-mercaptobenzothiazole has been prepared and characterized. The structure of the complexes has been assigned based on elemental analysis, IR, electronic spectral studies, magnetic measurement, molar conductance, Scanning electron microscope (S.E.M, X-ray powder diffraction techniques investigations and thermogravimetric analysis complete the characterization of the compound. Thermogravimetry(TG, derivative thermogravimetry (DTG and differential thermal analysis (DTA have been used to study the thermal decomposition of the complexes. The kinetic parameters have been calculated making use of the Coats-Redfern and Horowitz-Metzger. The scanning electron microscope SEM photographs and particle size calculations from the powder XRD data indicate the average size of the prepared UO2(II (28-56 nm supramolecular coordination polymers in the nanoscale range. The biological screening of the compounds was also tested.

  20. Chemical Composition and Antimicrobial Potential of Palm Leaf Extracts from Babaçu (Attalea speciosa), Buriti (Mauritia flexuosa), and Macaúba (Acrocomia aculeata)

    Science.gov (United States)

    Mahmoud, Talal Suleiman; do Nascimento, Guilherme Nobre L.; da Silva, Juliana Fonseca Moreira

    2016-01-01

    Babaçu (A. speciosa), Buriti (M. flexuosa), and Macaúba (A. aculeata) are palm trees typical of the ecotone area between Cerrado and the Amazon rainforest. The purpose of this study was to evaluate the antimicrobial potential of the extracts prepared from the leaves of those palms as well as determine their chemical compositions. The ethanol extracts were prepared in a Soxhlet apparatus and tested by disk diffusion and agar dilution technique against Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, Pseudomonas aeruginosa, Candida albicans, and Candida parapsilosis. However, there was no significant activity at concentrations of 25, 50, and 100 mg·Ml−1. Moreover, the phytochemical analysis revealed the presence of tannins, flavonoids, catechins, steroids, triterpenes, and saponins. Gas chromatography (GC/MS) analysis also identified organic acids, such as capric (decanoic) acid, lauric (dodecanoic) acid, myristic (tetradecanoic) acid, phthalic (1,2-benzenedicarboxylic) acid, palmitic (hexadecanoic) acid, stearic (octadecanoic) acid, linoleic (9,12-octadecadienoic) acid (omega-6), linolenic (octadecatrienoic) acid (omega-3), and the terpenes citronellol and phytol. Based on the chemical composition in the palm leaf extracts, the palms have the potential to be useful in the food, cosmetic, and pharmaceutical industries. PMID:27529077

  1. A new monoterpenoid glucoside from the twigs of Chamaecyparis obtusa var.breviramea f.crippsii%黄叶扁柏枝叶中的一个新单萜苷

    Institute of Scientific and Technical Information of China (English)

    徐健; 张玉梅; 陈科力; 谭宁华; 刘义梅

    2012-01-01

    为了研究黄叶扁柏(Chamaecyparis obtusa var.breviramea f.crippsii)的化学成分,用硅胶柱、Sephadex LH-20、C18反相硅胶柱色谱、制备液相等色谱方法从其枝叶中分离得到6个化合物,通过波谱方法将它们的结构分别鉴定为(4S)-4-isopropylcyclohex-1-enecarboxylic acid 4-O-β-D-glucopyranoside (1)、(4R)-p-menth- 1-ene-7,8-diol 7-O-β-D-glucopyranoside (2)、skimmin (3)、7-[[6-O-(6-deoxy-α-L-mannopyranosyl)-β-D-glucopyranosyl]oxy]-2H-1-benzopyran-2-one (4)、stigmast-4-en-3-one (5)和1,4-benzenedicarboxylic acid l-butyl-4-(2-methylpropyl) ester (6).其中化合物1为新化合物,化合物2~6为首次从该植物中分离得到.体外细胞毒活性筛选发现,黄叶扁柏枝叶的甲醇提取物在人A549、BGC-823、Du145和MDA-MB-231肿瘤细胞株上均显示一定的细胞毒活性,其IC50值分别为0.94、1.07、0.95和0.96 μg·mL-1,但化合物1、2和3在人HeLa、BGC-823和A549细胞株上均无明显细胞毒活性.%To investigate the chemical constituents of Chamaecyparis obtusa var. breviramea f. crippsii, various column chromatography and spectroscopic methods were used for the isolation and elucidation of compounds. One new monoterpenoid glucoside, (4S)-4-isopropylcyclohex-l-enecarboxylic acid 4-O-β-D-glucopyranoside (1), together with five known compounds, (4R)-p-menth-l-ene-7, 8-diol 7-O-β-D-glucopyranoside (2), skimmin (3), 7-[[6-O-(6-deoxy-α-Z-mannopyranosyl)-β-Z)-glucopyranosyl]oxy]-2H-1-benzopyran-2-one (4), stigmast-4-en-3-one (5) and 1, 4-benzenedicarboxylic acid l-butyl-4-(2-methylpropyl) ester (6) were isolated and identified from the twigs of this plant. All compounds were isolated from this plant for the first time. The methanol extract of this plant showed cytotoxicity on cancer cell lines A549, BGC-823, Dul45 and MDA-MB-231 with IC50 values of 0.94, 1.07, 0.95 and 0.96 μg·mL-1, respectively. Yet, compounds 1, 2 and 3 showed no cytotoxicity on cancer cell lines HeLa, BGC-823 and A549.

  2. Development of low-alcohol floral water mixed with extract from mugwort%复合型艾叶低醇驱蚊露的研制

    Institute of Scientific and Technical Information of China (English)

    张岳花; 曾平; 谢维跃; 汤志球; 李帜红; 黄向辉

    2013-01-01

    Objective To develop a low-alcohol floral water with long repellent time and low irritation. Meth-ods Using dimethyl phthalate 1,2- Benzenedicarboxylic acid ( BAAPE) as a mosquito repellent with addition of extracts from mugwort, mint and lavender in order to give the products antipruritic effect. The mixed problem was resolved with introduction of the PEG - 40 hydrogenated castor oil as a solubilizer. Results A low-alcohol floral water mixed with mugwort and the ethanol content below 25% was prepared. Tests showed that the mosquito repellent time of the product was more than 4. 7 hours,and the physical and chemical properties were in line with our company' s enterprise standards. Conclusion The product is suitable for using in home and travel because of its long repellent time and high safety.%目的 开发一种驱蚊时效长、刺激性低的低醇驱蚊露产品.方法 使用驱蚊酯作为蚊虫驱避剂,同时添加艾叶、薄荷、薰衣草天然植物提取物以赋予产品止痒健肤的功效,在配方中引入PEG-40氢化蓖麻油作为增溶剂解决混溶问题.结果 研制出一款乙醇含量在25%以下的复合型艾叶低醇驱蚊露,有效驱蚊时间达4.7h以上,各项理化指标均符合已制定的企业标准.结论 产品具有驱蚊时间长、安全性高的优点,适合各类人群居家及旅行使用.

  3. Ab initio and DFT study of the geometric structures and static dipole (hyper)polarizabilities of aromatic anions.

    Science.gov (United States)

    Castellano, O; Bermúdez, Y; Giffard, M; Mabon, G; Cubillan, N; Sylla, M; Nguyen-Phu, X; Hinchliffe, A; Soscún, H

    2005-11-17

    The geometries and the static dipole (hyper)polarizabilities (alpha, beta, gamma) of a series of aromatic anions were investigated at the ab initio (HF, MP2, and MP4) and density functional theory DFT (B3LYP) levels of theory. The anions chosen for the present study are the benzenethiolate (Ph-S-), benzenecarboxylate (Ph-CO2-), benzenesulfinate (Ph-SO2-), benzenesulfonate (Ph-SO3-), and 1,3-benzenedicarboxylate (1,3-Ph-(CO2)2(2-)). For benzenethiolate anion, additional alpha, beta, and gamma calculations were performed at the coupled cluster CCSD level with MP2 optimized geometries. The standard diffuse and polarized 6-31+G(d,p) basis set was employed in conjunction to the ab initio and DFT methods. Additional HF calculations were performed with the 6-311++G(3d,3p) basis set for all the anions. The correlated electric properties were evaluated numerically within the formalism of finite field. The optimized geometries were analyzed in terms of the few reports about the phenolate and sulfonate ions. The results show that electron correlation effects on the polarizabilities are very important in all the anion series. Was found that Ph-SO2- is highly polarizable in terms of alpha and beta, and the Ph-S- is the highest second hyperpolarizable in the series. The results of alpha were rationalized in terms of the analysis of the polarization of charge based in Mulliken atomic population and the structural features of the optimized geometries of anions, whereas the large differences in the beta and gamma values in the series were respectively interpreted in terms of the bond length alternation BLA and the separation of charge in the aromatic ring by effects of the substitution. These results allowed us to suggest the benzenesulfinate and benzenethiolate anions as promising candidates that should be incorporated in ionic materials for second and third-order nonlinear optical devices. PMID:16833334

  4. The SRAP based molecular diversity related to antifungal and antioxidant bioactive constituents for biocontrol potentials of Trichoderma against Sclerotium rolfsii Scc.

    Science.gov (United States)

    Hirpara, Darshna G; Gajera, H P; Bhimani, R D; Golakiya, B A

    2016-08-01

    The study was performed to examine 11 isolates of Trichoderma for their bio-control potentials against Sclerotium rolfsii Sacc. causing stem rot in groundnut. The antagonists Trichoderma were subjected to sequence related amplified polymorphism (SRAP) based molecular diversity analysis and compared with their hardness to S. rolfsii with respect to secretary antifungal and antioxidant profile. T. virens NBAII Tvs 12 evident highest (87.91 %) growth inhibition of test pathogen followed by T. koningii MTCC 796 (67.03 %) at 7 days after inoculation (DAI). Microscopic study confirmed biocontrol mechanism as mycoparasitism for Tvs 12 and antibiosis for MTCC 796. The growth inhibition of test pathogen was significantly negatively correlated with sclerotia formation and lipid peroxidation during antagonism due to release of secretary bioactive antioxidants by antagonists to terminate oxidative burst generated by S. rolfsii and causing inhibition of sclerotium formation. The GC-MS profile identified antifungal and antioxidant constituents hexadecane, 1,2-benzenedicarboxylic acid, mono (2-ethylhexyl) ester, 1-hexadecanesulfonyl chloride, and octadecane in potent antagonists Tvs 12; and nonacosane and octadecane in MTCC 796 along with two novel compounds 1-pentadecene and 1-heneicosyl formate for biocontrol activity. Molecular diversity of Trichoderma isolates associated with antagonistic activity was assessed by SRAP markers. The 115 primer combinations generate total 1328 amplified products of which, 1095 are shared polymorphic and 199 are unique polymorphic. The 15 SRAP combinations produced 18 bands to diagnose best antagonist Tvs 12 and 13 SRAP combinations generated 19 unique bands for identification of MTCC 796. The mycoparasitic antagonist Tvs 12 would be the best antagonist and released unique antifungal and antioxidant constituents to combat pathogen infection. The SRAP based genetic diversity indicates Tvs12 strain clustered with T. viride NBAII Tv23 and shared

  5. Fluorescent sensing and electrocatalytic properties of three Zn(II)/Co(II) coordination complexes containing two different dicarboxylates and two various bis(pyridyl)-bis(amide) ligands

    Science.gov (United States)

    Lin, Hongyan; Rong, Xing; Liu, Guocheng; Wang, Xiang; Wang, Xiuli; Duan, Surui

    2016-09-01

    Three new transition metal(II) coordination complexes constructed from two different dicarboxylates (1,3-H2BDC = 1,3-benzenedicarboxylic acid, 1,4-H2NDC = 1,4-naphthalenedicarboxylic acid) and two bis(pyridyl)-bis(amide) ligands (3-bpcd = N,N‧-bis(3-pyridyl)cyclohexane-1,4-dicarboxamide, 3-bpod = N,N‧-bis(3-pyridyl)octandiamide), [Zn(1,3-BDC)(3-bpcd)0.5(H2O)]·H2O (1), [Zn(1,3-BDC)(3-bpod)0.5(H2O)] (2) and [Co(1,4-NDC)(3-bpod)1.5(H2O)] (3) have been synthesized in the hydrothermal environments and structurally characterized by IR, TG and single crystal X-ray diffraction. Complexes 1 and 2 possess the similar 1D ladder-like chain based on [Zn(1,3-BDC)]n zigzag chain and the bidentate ligands 3-bpcd/or 3-bpod. Complex 3 shows a 2D layered structure with a 5-connected {410} topology, which consists of 1D linear [Co(1,4-NDC)]n chain and [Co(3-bpod)1.5]n chain with alternating arrangement of 3-bpod ligands and Co2(3-bpod)2 dinuclear loops. The adjacent 1D chains for 1-2 or the 2D layers for 3 are further extended into 2D or 3D supramolecular frameworks through the hydrogen bonding interactions. Additionally, the solid state fluorescent properties for the title complexes 1-3, the fluorescent sensing behaviors of complexes 1-2 and the electrochemical behaviour of complex 3 have been investigated.

  6. Role of seminal plasma in the anti-HIV-1 activity of candidate microbicides

    Directory of Open Access Journals (Sweden)

    Li Yun-Yao

    2006-10-01

    Full Text Available Abstract Background Evaluation of microbicides for prevention of HIV-1 infection in macaque models for vaginal infection has indicated that the concentrations of active compounds needed for protection by far exceed levels sufficient for complete inhibition of infection in vitro. These experiments were done in the absence of seminal plasma (SP, a vehicle for sexual transmission of the virus. To gain insight into the possible effect of SP on the performance of selected microbicides, their anti-HIV-1 activity in the presence, and absence of SP, was determined. Methods The inhibitory activity of compounds against the X4 virus, HIV-1 IIIB, and the R5 virus, HIV-1 BaL was determined using TZM-bl indicator cells and quantitated by measuring β-galactosidase induced by infection. The virucidal properties of cellulose acetate 1,2-benzene-dicarboxylate (CAP, the only microbicide provided in water insoluble, micronized form, in the presence of SP was measured. Results The HIV-1 inhibitory activity of the polymeric microbicides, poly(naphthalene sulfonate, cellulose sulfate, carrageenan, CAP (in soluble form and polystyrene sulfonate, respectively, was considerably (range ≈ 4 to ≈ 73-fold diminished in the presence of SP (33.3%. Formulations of micronized CAP, providing an acidic buffering system even in the presence of an SP volume excess, effectively inactivated HIV-1 infectivity. Conclusion The data presented here suggest that the in vivo efficacy of polymeric microbicides, acting as HIV-1 entry inhibitors, might become at least partly compromised by the inevitable presence of SP. These possible disadvantages could be overcome by combining the respective polymers with acidic pH buffering systems (built-in for formulations of micronized CAP or with other anti-HIV-1 compounds, the activity of which is not affected by SP, e.g. reverse transcriptase and zinc finger inhibitors.

  7. Synthesis, crystal structures and properties of lanthanide-organic frameworks based benzene carboxylates with two/three-dimensional structure

    International Nuclear Information System (INIS)

    A series of lanthanide coordination polymers, {[Dy3(1,3-BDC)4(NO3)(phen)3]·2H2O}n (1), {[Dy2(1,3-BDC)3(H2O)2]·H2O}n (2), {[Ln4(1,3-BDC)6(DMF)(H2O)4]·DMF·2H2O}n (Ln=Tb (3), Ho (4), Er (5), 1,3-H2BDC=1,3-benzenedicarboxylate, phen=1,10-phenanthroline, DMF=N,N-dimethylformamide), have been synthesized and characterized. In coordination polymer 1, each Dy3+ ion is connected to its neighboring Dy3+ ion through bridging carboxyl oxygen atoms of the 1,3-BDC2− ligands to form a new three-dimensional open-framework structure which the Schläfli symbol of {64·82}2{66}. In coordination polymer 2, center metal dysprosium ions are interlaced and connected through bridging carboxyl oxygen atoms to form an infinite helix chain. Two helix chains are linked through the 1,3-BDC2− ligand to give rise to the two-dimensional layered structure. Coordination polymers 3–5 are isomorphous, which displays a (3,4)-connected net with the point symbol of {42·63·8}{42·6}. The solid-state photoluminescence properties and lifetimes of the Dy (1 and 2) and Tb (3) coordination polymers have been measured at room temperature. Highlights: ► Five lanthanide coordination polymers based on 1,3-H2BDC were obtained. ► The polymers were structurally characterized by single-crystal X-ray diffraction. ► Coordination polymers 1–5 display different topological structures. ► They show characteristic emissions of lanthanide ions in the solid state.

  8. Cadmium(Ⅱ) Nitrite Complex Based on the Bis(2-benzimidazole) and Aromatic Carboxylate Ligands%Cadmium(Ⅱ) Nitrite Complex Based on the Bis(2-benzimidazole) and Aromatic Carboxylate Ligands

    Institute of Scientific and Technical Information of China (English)

    JIANG Luan; FENG Guo-Dong; CHEN Qiang; YANG De-Suo; LI Zong-Xiao; LUO Xiao-Lin

    2012-01-01

    A new cadmium(Ⅱ) nitrite complex Cd2(H2C3PIm)2(BDC)(NO2)2(1,H2C3PIm = 2,2'-(1,3-propanediyl)bis(1H-benzimidazole),H2BDC = 1,4-benzenedicarboxylic acid) has been synthesized by solvothermal reaction in formamide,and its structure(C42H36Cd2N10O8,Mr = 1033.61) was determined by single-crystal X-ray diffraction analysis.The crystal belongs to the monoclinic system,space group P21/n with a = 0.9859(5),b = 0.8936(5),c = 2.3188(5) nm,β = 97.576(5)°,V = 2.025(16) nm3,Z = 2,Dc = 1.695 g/cm3,μ(MoKα) = 1.118 mm-1,F(000) = 1036,S = 1.017,the final R = 0.0304 and wR = 0.0752 for 3761 reflections with I 〉 2σ(I).The centrosymmetric complex 1 contains a dimer in which two distorted octahedral Cd(II) centers are bridged by BDC ligand and chelated by H2C3PIm.The units of the complex are linked via weak N-H···O hydrogen bonds between the nitrito and the BDC ligands,leading to the formation of a 1D zigzag chain along the b axis.The π-π packing interactions contribute to the formation of a three-dimensional supramolecular architecture.The complex exhibits strong photoluminescence at room temperature.

  9. Structural and Electronic Effects on the Properties of Fe2(dobdc) upon Oxidation with N2O.

    Science.gov (United States)

    Borycz, Joshua; Paier, Joachim; Verma, Pragya; Darago, Lucy E; Xiao, Dianne J; Truhlar, Donald G; Long, Jeffrey R; Gagliardi, Laura

    2016-05-16

    We report electronic, vibrational, and magnetic properties, together with their structural dependences, for the metal-organic framework Fe2(dobdc) (dobdc(4-) = 2,5-dioxido-1,4-benzenedicarboxylate) and its derivatives, Fe2(O)2(dobdc) and Fe2(OH)2(dobdc)-species arising in the previously proposed mechanism for the oxidation of ethane to ethanol using N2O as an oxidant. Magnetic susceptibility measurements reported for Fe2(dobdc) in an earlier study and reported in the current study for Fe(II)0.26[Fe(III)(OH)]1.74(dobdc)(DMF)0.15(THF)0.22, which is more simply referred to as Fe2(OH)2(dobdc), were used to confirm the computational results. Theory was also compared to experiment for infrared spectra and powder X-ray diffraction structures. Structural and magnetic properties were computed by using Kohn-Sham density functional theory both with periodic boundary conditions and with cluster models. In addition, we studied the effects of different treatments of the exchange interactions on the magnetic coupling parameters by comparing several approaches to the exchange-correlation functional: generalized gradient approximation (GGA), GGA with empirical Coulomb and exchange integrals for 3d electrons (GGA+U), nonseparable gradient approximation (NGA) with empirical Coulomb and exchange integrals for 3d electrons (NGA+U), hybrid GGA, meta-GGA, and hybrid meta-GGA. We found the coupling between the metal centers along a chain to be ferromagnetic in the case of Fe2(dobdc) and antiferromagnetic in the cases of Fe2(O)2(dobdc) and Fe2(OH)2(dobdc). The shift in magnetic coupling behavior correlates with the changing electronic structure of the framework, which derives from both structural and electronic changes that occur upon metal oxidation and addition of the charge-balancing oxo and hydroxo ligands. PMID:27136308

  10. Thermodynamics of solvent interaction with the metal-organic framework MOF-5.

    Science.gov (United States)

    Akimbekov, Zamirbek; Wu, Di; Brozek, Carl K; Dincă, Mircea; Navrotsky, Alexandra

    2016-01-14

    The inclusion of solvent in metal-organic framework (MOF) materials is a highly specific form of guest-host interaction. In this work, the energetics of solvent MOF-5 interactions has been investigated by solution calorimetry in 5 M sodium hydroxide (NaOH) at room temperature. Solution calorimetric measurement of enthalpy of formation (ΔH(f)) of Zn4O(C8H4O4)3·C3H7NO (MOF-5·DMF) and Zn4O(C8H4O4)3·0.60C5H11NO (MOF-5·0.60DEF) from the dense components zinc oxide (ZnO), 1,4-benzenedicarboxylic acid (H2BDC), N,N-dimethylformamide (DMF) and N,N-diethylformamide (DEF) gives values of 16.69 ± 1.21 and 45.90 ± 1.46 kJ (mol Zn4O)(-1), respectively. The enthalpies of interaction (ΔH(int)) for DMF and DEF with MOF-5 are -82.78 ± 4.84 kJ (mol DMF)(-1) and -89.28 ± 3.05 kJ (mol DEF)(-1), respectively. These exothermic interaction energies suggest that, at low guest loading, Lewis base solvents interact more strongly with electron accepting Zn4O clusters in the MOF than at high solvent loading. These data provide a quantitative thermodynamic basis to investigate transmetallation and solvent assisted linker exchange (SALE) methods and to synthesize new MOFs. PMID:26658672

  11. Source reconciliation of atmospheric gas-phase and particle-phase pollutants during a severe photochemical smog episode.

    Science.gov (United States)

    Schauer, James J; Fraser, Matthew P; Cass, Glen R; Simoneit, Bernd R T

    2002-09-01

    concentrations of 1,2-benzenedicarboxylic acid in the atmospheric fine particle mass, indicating that aromatic diacids may be useful in the quantification of certain sources of secondary organic aerosol in the atmosphere. PMID:12322754

  12. A two-dimensional yttrium phthalate coordination polymer, [Y4(H2O)2(C8H4O4)6]∞, exhibiting different coordination geometries

    Indian Academy of Sciences (India)

    A Thirumurugan; Srinivasan Natarajan

    2003-10-01

    A hydrothermal reaction of a mixture of Y(NO3)3, 1,2-benzenedicarboxylic acid (1,2-BDC) and NaOH gives rise to a new yttrium phthalate coordination polymer, [Y4(H2O)2(C8H4O4)6]∞, I. The Y ions in I are present in four different coordination environments with respect to the oxygen atoms (CN6 = octahedral, CN7 = pentagonal bipyramid, CN8 = dodecahedron and CN9 =capped square antiprism). The oxygen atoms of the 1,2-BDC are fully deprotonated, and show variations in their connectivity with Y atoms. The Y atoms themselves are connected through their vertices forming infinite Y-O-Y one-dimensional chains. The Y-O-Y chains are cross-linked by the 1,2-BDC anions forming a corrugated layer structure. The layers are supported by favourable $\\ldots$ interactions between the benzene rings of the 1,2-BDC anions. The variations in the coordination environment of the Y atoms and the presence of Y-O-Y interactions along with the favourable $\\ldots$ interactions between the benzene rings from different layers are noteworthy structural features. Crystal data: triclinic, space group = -1 (no. 2), = 12.6669 (2), = 13.8538 (2), = 16.0289 Å, = 75.20 (1), = 69.012 (1), = 65.529 (1)°, = 2371.28 (7) Å3, calc = 1.922 g cm-1, (MoK) = 4.943 mm-1. A total of 9745 reflections collected and merged to give 6566 unique reflections (int = 0.0292) of which 5252 with > 2() were considered to be observed. Final 2 = 0.0339, 2 = 0.0724 and =1.036 were obtained for 704 parameters.

  13. Combined study of structural properties on metal-organic frameworks with same topology but different linkers or metal

    International Nuclear Information System (INIS)

    The recently discovered UiO-66/67/68 class of isostructural metallorganic frameworks (MOFs) [2008 J. Am. Chem. Soc. 130 13850] has attracted great interest because of its remarkable stability at high temperatures, high pressures and in presence of different solvents acids and bases [2011 Chem. Mater. 23 1700]. UiO-66 is obtained connecting Zr6O4(OH)4 inorganic cornerstones with 1,4-benzene-dicarboxylate (BDC) linkers, while for the isostructural UiO-67, the longer 4,4' biphenyl-dicarboxylate (BPDC) is used as linker [2012 Phys. Chem. Chem. Phys. 14 1614]. Hf-UiO-66 is built with the same linker of UiO-66 but, in this case, Hf6O4(OH)4 blocks substitute the Zr6O4(OH)4 ones [2012, Phys. Rev. B 86 125429]. In all cases isostructural cubic MOFs are obtained. Here we report a systematic EXAFS investigation of UiO-66 and UiO-67 (at Zr L3-edge) and of Hf-UiO-66 (at Hf L3-edge) before and after the removal of solvent in their pores, needed to make the channel volume available. The study reveals that, for the three systems, the perfect M6O4(OH)4 (M = Zr or Hf) octahedron forming the cornerstones of the as prepared material undergoes a remarkable local rearrangement into a distorted M6O6 octahedron, with the loss of two water molecules under the desolvation process. Notwithstanding the high crystallinity of the materials, this rearrangement, moving M atoms from 8-fold to 7-fold coordination and distorting the M-M distance of the octahedron side by more than 0.2 Å, escape XRPD detection (because not ordered on the long range scale) but is clearly observed by EXAFS owing to its local sensitivity.

  14. Molecular tectonics of mixed-ligand metal-organic frameworks: Positional isomeric effect, and structural diversification

    Science.gov (United States)

    Cai, Hua; Xu, Chong; Zhou, Yu-Ping; Tong, Xiao-Qiang; Guo, Ying

    2016-03-01

    To explore the influence of three structurally different polycarboxylate ligands H2L1 to H4L3 in the system Cd(II)/PPAN, three coordination polymers, formulated as {Cd2(PPAA)2(L1)2}n (1), {[Cd2(PPAA)2(HL2) (H2O)].2H2O}n (2), {Cd2(PPAN)2(L3) (H2O)2}n (3) have been obtained under similar conditions (PPAA- = 2-(3-(pyridin-2-yl)-1H-pyrazol-1-yl)acetate, PPAN = 2-(3-(pyridin-2-yl)-1H-pyrazol-1-yl)acetonitrile, H2L1 = 1,3-benzenedicarboxylic acid, H3L2 = 1,3,5-benzenetricarboxylic acid, H4L3 = 1,2,4,5-benzenetetracarboxylic acid). In 1-2, PPAN are hydrolyzed into a novel PPAA- ligand. The structure determination reveals that complex 1 contains 1D double chains of {[Cd(PPAA)]+}n cation structural units, which are further extended by these μ3-(L1)2- ligands forming a novel 2D three-layered framework with (4.82)2(43.62.8)2(4383)2(48.66.8) topology. Complex 2 is one-dimensional (1D) ribbon-like chains having two kinds of dimerics [Cd(PPAA)]2 and [Cd(COO)]2 subunits and dimeric Cd(II) units bridged by μ3-(HL2)2- ligands. Complex 3 shows an undulating 2D (4, 4)-network by μ4-(L3)4-. In addition, photoluminescent properties of three coordination polymers were also investigated in this paper.

  15. Molecular simulations of adsorption of RDX and TATP on IRMOF-1(Be)

    Energy Technology Data Exchange (ETDEWEB)

    Petrova, Tetyana [Jackson State University; Odbadrakh, Khorgolkhuu [ORNL; Fuentes-Cabrera, Miguel A [ORNL; Lewis, James [West Virginia University; Leszczynski, Jerzy [Computational Center for Molecular Structure and Interactions, Jackson, MS

    2012-01-01

    The influence of different sorption sites of isoreticular metal-organic frameworks (IRMOFs) on interactions with explosive molecules is investigated. Different connector effects are taken into account by choosing IRMOF-1(Be) (IRMOF-1 with Zn replaced by Be), and two high explosive molecules: 1,3,5-trinitro-s-triazine (RDX) and triacetone triperoxide (TATP). The key interaction features (structural, electronic and energetic) of selected contaminants were analyzed by means of density functional calculations. The interaction of RDX and TATP with different IRMOF-1(Be) fragments is studied. The results show that physisorption is favored and occurs due to hydrogen bonding, which involves the C-H groups of both molecules and the carbonyl oxygen atoms of IRMOF-1(Be). Additional stabilization of RDX and TATP arises from weak electrostatic interactions. Interaction with IRMOF-1(Be) fragments leads to polarization of the target molecules. Of the molecular configurations we have studied, the Be-O-C cluster connected with six benzene linkers (1,4-benzenedicarboxylate, BDC), possesses the highest binding energy for the studied explosives (-16.4 kcal mol-1 for RDX and -12.9 kcal mol-1 for TATP). The main difference was discovered to be in the preferable adsorption site for adsorbates (RDX above the small and TATP placed above the big cage). Based on these results, IRMOF-1 can be suggested as an effective material for storage and also for separation of similar explosives. Hydration destabilizes most of the studied adsorption systems by 1-3 kcal mol-1 but it leads to the same trend in the binding strength as found for the non-hydrated complexes.

  16. Synthesis, characterizations and catalytic studies of a new two-dimensional metal−organic framework based on Co–carboxylate secondary building units

    International Nuclear Information System (INIS)

    A metal–organic framework [Co3(BDC)3(DMF)2(H2O)2] was synthesized and structurally characterized. X-ray single crystal analysis revealed that the framework contains a 2D polymeric chain through coordination of 1,4-benzenedicarboxylic acid linker ligand to cobalt centers. The polymer crystallize in monoclinic P21/n space group with a=13.989(3) Å, b=9.6728(17) Å, c=16.707(3) Å, and Z=2. The polymer features a framework based on the perfect octahedral Co–O6 secondary building units. The catalytic activities of [Co3(BDC)3(DMF)2(H2O)2]n for olefins oxidation was conducted. The heterogeneous catalyst could be facilely separated from the reaction mixture, and reused three times without significant degradation in catalytic activity. Furthermore, no contribution from homogeneous catalysis of active species leaching into reaction solution was detected. - Graphical abstract: A metal–organic framework of [Co3(BDC)3(DMF)2(H2O)2] was synthesized by hydrothermal method. This 2D-periodic framework is constructed from the infinite Co–O–C secondary building units and crystallizes in the monoclinic P21/n space group based on Co(II)–carboxylate units. The catalytic oxidation of various olefins was effectively carried out with [Co3(BDC)3(DMF)2(H2O)2]n catalyst by TBHP as oxidant. - Highlights: • A metal–organic framework of [Co3(BDC)3(DMF)2(H2O)2] is prepared by hydrothermal method. • The [Co3(BDC)3(DMF)2(H2O)2]n is constructed from Co–carboxylate secondary building units. • This coordination polymer displayed high catalytic activity for olefin oxidation reactions. • The catalytic reaction is heterogeneous and catalyst can be simply separated. • The heterogeneous catalyst can be reused several times without significant loss of catalytic activity

  17. Mechanism of electrochemical lithiation of a metal-organic framework without redox-active nodes.

    Science.gov (United States)

    Tang, Bohejin; Huang, Shuping; Fang, Yuan; Hu, Jinbo; Malonzo, Camille; Truhlar, Donald G; Stein, Andreas

    2016-05-21

    Metal-organic frameworks (MOFs) have many potential uses for separations, storage, and catalysis, but their use as intercalation hosts for batteries has been scarce. In this article, we examine the mechanism of Li insertion in a MOF to provide guidance to future design efforts in this area. As a model system, we choose UiO-66, a MOF with the formula (Zr6O4(OH)4)4(1,4-benzenedicarboxylate)6, as an electrode material for lithium-ion batteries; this MOF is of special interest because the zirconium is not redox active. We report both quantum mechanical characterization of the mechanism and experimental studies in which the material is synthesized as nanoparticles to reduce diffusion lengths for lithium ions and increase the contact area with a conductive carbon phase. The calculated changes in the IR spectra of UiO-66 and lithiated UiO-66 are consistent with the experimental FTIR results. We found experimentally that this MOF can maintain a specific discharge capacity of at least 118 mAh/g for 30 lithiation and delithiation cycles at a rate of C/5, exhibiting good cyclability. Density functional electronic structure calculations show that the charge transfer during lithiation is mainly from Li to node oxygens and carboxylate oxygens, that is, it involves anions rather than cations or aromatic rings, and they provide a mechanistic understanding of the potential for increased Li capacity because the theoretical capacity of UiO-66 with Li at the oxygens in the metal oxide nodes and the carboxylate linkers is more than 400 mAh/g. The lithiation process greatly decreases the bandgap of UiO-66, which is expected to increase its electronic conductivity. The electrode material was also characterized by X-ray diffraction and scanning electron microscopy, which were consistent in confirming that smaller particle sizes were obtained in lower-temperature syntheses. PMID:27208960

  18. Adsorption and separation of CO2 on Fe(II)-MOF-74: Effect of the open metal coordination site

    International Nuclear Information System (INIS)

    We describe the successful synthesis of Fe2(dobdc) (dobdc4−=2, 5-dioxido-1, 4-benzenedicarboxylate), which has an open metal coordination site Fe(II), and investigate the adsorption properties of three important molecules CO2, CH4 and N2 on Fe2(dobdc) and an oxidized analog, Fe2(O2)(dobdc). We found that CO2 adsorption isotherm of Fe2(dobdc) at 10 bar was very different from Fe2(O2)(dobdc), with the capacities of 144.5 cm3 g−1 and 98.1 cm3 g−1, respectively. The adsorption capacities for CH4 were 75.8 cm3 g−1 and 36.8 cm3 g−1, respectively, at 10 bar in these materials. Using ideal adsorbed solution theory (IAST), we obtain the adsorption selectivity for CO2 using equimolar mixtures of CO2/CH4 and CO2/N2 with Fe2(dobdc) and Fe2(O2)(dobdc) as a function of pressure. Fe2(dobdc) has a higher, more stable separation factor. - Graphical abstract: The selectivity of CO2/CH4 mixture (50%/50%) on Fe2(dobdc) and Fe2(O2)(dobdc). - Highlights: • We explored the contrastive adsorption of CO2, CH4, and N2 in Fe2(dobdc) and Fe2(O2)(dobdc) for the first time. • Through IAST, we obtain the adsorption selectivity for CO2 from the equimolar mixture of CO2/CH4 and CO2/N2 for Fe2(dobdc) and Fe2(O2)(dobdc). • We determined that the open coordination site of Fe(II) is the main reason for different adsorption performances

  19. MIL-53(Fe) as a highly efficient bifunctional photocatalyst for the simultaneous reduction of Cr(VI) and oxidation of dyes

    Energy Technology Data Exchange (ETDEWEB)

    Liang, Ruowen; Jing, Fenfen; Shen, Lijuan; Qin, Na; Wu, Ling, E-mail: wuling@fzu.edu.cn

    2015-04-28

    Highlights: • Fe(III)-based MOF was firstly applied to the photocatalytic reduction reaction. • MIL-53(Fe) exhibited an outstanding photocatalytic activity for reduction of Cr(VI). • A first systematic study of the Fe(III)-based MOF as bifunctional photocatalyst. • Dyes and Cr(VI) could be also converted simultaneously over MIL-53(Fe). • MIL-53(Fe) was performed a stable and reusable visible-light-driven photocatalyst. - Abstract: A bifunctional photocatalyst-Fe-benzenedicarboxylate (MIL-53(Fe)) has been synthesized successfully via a facile solvothermal method. The resulting MIL-53(Fe) photocatalyst exhibited an excellent visible light (λ ≥ 420 nm) photocatalytic activity for the reduction of Cr(VI), the reduction rate have reached about 100% after 40 min of visible light irradiation, which has been more efficient than that of N-doped TiO{sub 2} (85%) under identical experimental conditions. Further experimental results have revealed that the photocatalytic activity of MIL-53(Fe) for the reduction of Cr(VI) can be drastically affected by the pH value of the reaction solution, the hole scavenger and atmosphere. Moreover, MIL-53(Fe) has exhibited considerable photocatalytic activity in the mixed systems (Cr(VI)/dyes). After 6 h of visible light illumination, the reduction ratio of Cr(VI) and the degradation ratio of dyes have been exceed 60% and 80%, respectively. More significantly, the synergistic effect can also be found during the process of photocatalytic treatment of Cr(VI) contained wastewater under the same photocatalytic reaction conditions, which makes it a potential candidate for environmental restoration. Finally, a possible reaction mechanism has also been investigated in detail.

  20. UTSA-74: A MOF-74 Isomer with Two Accessible Binding Sites per Metal Center for Highly Selective Gas Separation.

    Science.gov (United States)

    Luo, Feng; Yan, Changsheng; Dang, Lilong; Krishna, Rajamani; Zhou, Wei; Wu, Hui; Dong, Xinglong; Han, Yu; Hu, Tong-Liang; O'Keeffe, Michael; Wang, Lingling; Luo, Mingbiao; Lin, Rui-Biao; Chen, Banglin

    2016-05-01

    A new metal-organic framework Zn2(H2O)(dobdc)·0.5(H2O) (UTSA-74, H4dobdc = 2,5-dioxido-1,4-benzenedicarboxylic acid), Zn-MOF-74/CPO-27-Zn isomer, has been synthesized and structurally characterized. It has a novel four coordinated fgl topology with one-dimensional channels of about 8.0 Å. Unlike metal sites in the well-established MOF-74 with a rod-packing structure in which each of them is in a five coordinate square pyramidal coordination geometry, there are two different Zn(2+) sites within the binuclear secondary building units in UTSA-74 in which one of them (Zn1) is in a tetrahedral while another (Zn2) in an octahedral coordination geometry. After activation, the two axial water molecules on Zn2 sites can be removed, generating UTSA-74a with two accessible gas binding sites per Zn2 ion. Accordingly, UTSA-74a takes up a moderately high and comparable amount of acetylene (145 cm(3)/cm(3)) to Zn-MOF-74. Interestingly, the accessible Zn(2+) sites in UTSA-74a are bridged by carbon dioxide molecules instead of being terminally bound in Zn-MOF-74, so UTSA-74a adsorbs a much smaller amount of carbon dioxide (90 cm(3)/cm(3)) than Zn-MOF-74 (146 cm(3)/cm(3)) at room temperature and 1 bar, leading to a superior MOF material for highly selective C2H2/CO2 separation. X-ray crystal structures, gas sorption isotherms, molecular modeling, and simulated and experimental breakthroughs comprehensively support this result. PMID:27113684

  1. Synthesis, characterization and sorption properties of functionalized Cr-MIL-101-X (X=-F, -Cl, -Br, -CH3, -C6H4, -F2, -(CH3)2) materials

    Science.gov (United States)

    Buragohain, Amlan; Couck, Sarah; Van Der Voort, Pascal; Denayer, Joeri F. M.; Biswas, Shyam

    2016-06-01

    Four existing and three new functionalized chromium terephthalates having MIL-101 topology and denoted as Cr-MIL-101-X (existing ones with X=-F, 1-F; -Cl, 2-Cl; -Br, 3-Br; -CH3, 4-CH3; new ones with X=-C6H4, 5-C6H4; -F2, 6-F2, -(CH3)2, 7-(CH3)2) were synthesized under hydrothermal conditions. All the materials except 5-C6H4 could be prepared by a general synthetic route, in which the mixtures of CrO3, H2BDC-X (BDC=1,4-benzenedicarboxylate) linkers, conc. HCl and water with a molar ratio of 1:1:3.9:222.2 were reacted at 180 °C for 144 h. Compared to the 144 h of synthesis time, three of the compounds, namely 1-Cl, 2-Br and 5-C6H4, could be prepared in much shorter reaction times (12-18 h at 180-210 °C). The materials possess high thermal stability up to 270-300 °C in an air atmosphere. The activated compounds exhibit significant porosity (SBET range: 1273-2135 m2 g-1). At 0 °C and 1 bar, the CO2 adsorption capacities of the compounds fall in the 1.7-2.9 mmol g-1 range. Compounds 1-F and 6-F2 showed enhanced CO2 uptake values compared to parent Cr-MIL-101. The benzene adsorption capacities of the compounds lie in the range of 66.2-139.5 molecules per unit cell at 50 °C and p/p0=0.35. The increased benzene uptake value of 1-F compared to un-functionalized Cr-MIL-101 and 4-CH3 suggests that the fluorination has induced more hydrophobicity in Cr-MIL-101 as compared to the methylation.

  2. Growth, Fatty Acid, and Lipid Composition of Marine Microalgae Skeletonema costatum Available in Bangladesh Coast: Consideration as Biodiesel Feedstock

    Directory of Open Access Journals (Sweden)

    Tania Sharmin

    2016-01-01

    Full Text Available Among the various potential sources of renewable energy, biofuels are of most interest. Marine microalgae are the most promising oil sources for making biofuels, which can grow very rapidly and convert solar energy to chemical energy via CO2 fixation. The fatty acid profile of almost all the microalgal oil is suitable for the synthesis of biofuel. In this research, fatty acid and lipid contents of Bangladeshi strains of marine microalgae Skeletonema costatum were performed. For this, the crude oil was extracted by Soxhlet extraction method, using three most common solvent systems, pure hexane and mixture of CHCl3 : MeOH (2 : 1 and hexane : EtOH (3 : 1 one by one. Highest oil recovery (15.37% came from CHCl3 : MeOH (2 : 1 solvent system from dry biomass whereas the lowest (2.49% came from n-hexane from wet biomass. The qualitative analysis of the extracted oil by GC/MS analysis revealed that it contained significant amount of myristic acid (C14:0, palmitic acid (C16:0, stearic acid (C18:0, and palmitoleic acid (C16:1. It also indicated presence of hexadecatrienoic acid, benzenedicarboxylic acid, oleic acid, arachidonic acid, eicosapentaenoic acid (EPA, 9-Octadecenoic acid methyl ester (C19H36O2, and so forth. The obtained fatty acid profile indicates high potentiality of S. costatum species to be used as promising biofuel feedstock a little improvisation and substantially it can replace diesel in near future.

  3. Mechanism of electrochemical lithiation of a metal-organic framework without redox-active nodes

    Science.gov (United States)

    Tang, Bohejin; Huang, Shuping; Fang, Yuan; Hu, Jinbo; Malonzo, Camille; Truhlar, Donald G.; Stein, Andreas

    2016-05-01

    Metal-organic frameworks (MOFs) have many potential uses for separations, storage, and catalysis, but their use as intercalation hosts for batteries has been scarce. In this article, we examine the mechanism of Li insertion in a MOF to provide guidance to future design efforts in this area. As a model system, we choose UiO-66, a MOF with the formula (Zr6O4(OH)4)4(1,4-benzenedicarboxylate)6, as an electrode material for lithium-ion batteries; this MOF is of special interest because the zirconium is not redox active. We report both quantum mechanical characterization of the mechanism and experimental studies in which the material is synthesized as nanoparticles to reduce diffusion lengths for lithium ions and increase the contact area with a conductive carbon phase. The calculated changes in the IR spectra of UiO-66 and lithiated UiO-66 are consistent with the experimental FTIR results. We found experimentally that this MOF can maintain a specific discharge capacity of at least 118 mAh/g for 30 lithiation and delithiation cycles at a rate of C/5, exhibiting good cyclability. Density functional electronic structure calculations show that the charge transfer during lithiation is mainly from Li to node oxygens and carboxylate oxygens, that is, it involves anions rather than cations or aromatic rings, and they provide a mechanistic understanding of the potential for increased Li capacity because the theoretical capacity of UiO-66 with Li at the oxygens in the metal oxide nodes and the carboxylate linkers is more than 400 mAh/g. The lithiation process greatly decreases the bandgap of UiO-66, which is expected to increase its electronic conductivity. The electrode material was also characterized by X-ray diffraction and scanning electron microscopy, which were consistent in confirming that smaller particle sizes were obtained in lower-temperature syntheses.

  4. Spectroscopic properties of a series of Co(II) coordination polymers and the influence of Co(II) coordination environment on photoelectric property

    Science.gov (United States)

    Jin, Jing; Gong, Yuanyuan; Li, Lei; Han, Xiao; Meng, Qin; Liu, Yonghua; Niu, Shuyun

    2015-02-01

    Four Co(II) coordination polymers, [Co(suc)]n1, [Co(pdc)]n2, {[Co7(suc)4(OH)6(H2O)3] · 8H2O}n3, {[Co(bdc)(phen)(H2O)] · H2O}n4 (H2suc = succinic acid, H2pdc = pyridine-3,4-dicarboxylic acid, H2bdc = 1,2-benzenedicarboxylic acid, phen = 1,10-phenanthroline) were hydrothermally synthesized and characterized by X-ray single-crystal diffraction, surface photovoltage spectroscopy (SPS), electrical conductivity, thermogravimetric analysis (TG), ultraviolet visible and near-infrared absorption spectrum (UV-Vis-NIR), infrared spectrum (IR), and elemental analysis. The structural analyses indicate that the coordination numbers of the Co(II) ions are 4, 5, 6 and 6 for the polymers 1-4, respectively. And polymers 1 and 2 exhibit 3D structure formed by suc2- and pdc2- anions bridging Co(II) ions, respectively. Polymer 3 exhibits a 2D structure with suc2- anions bridging seven-nuclear [Co7(OH)6(H2O)3]3- unit and polymer 4 is a 1D structure bridged by bdc2- anions. The surface photoelectric properties of the cobalt polymers were mainly studied by SPS. The results of SPS reveal that all polymers possess certain photoelectric conversion property in the range of 300-800 nm. The influences of the structure, coordination micro-environment of central metal ion and structural dimensionality on response bands of SPS were discussed.

  5. Activity-guided isolation and identification of anti-staphylococcal components from Senecio tenuifolius Burm. F. leaf extracts

    Institute of Scientific and Technical Information of China (English)

    Manjunath Manubolu; Lavanya Goodla; Sivajyothi Ravilla; Vijayasarathi Reddy Obulum

    2013-01-01

    Objective: To investigate activity-guided isolation and identification of anti-Staphylococcus aures components from Senecio tenuifolius Burm. F. (S. tenuifolius). Methods: Hexane, chloroform, ethyl acetate, methanol and aqueous extracts of S. tenuifolius were prepared by soxilation for antimicrobial activity against one registered Staphylococcus aureus (S. aureus) (ATCC No: 25923) and two clinical isolates, methicillin resistant and methicillin sensitive S. aureus. NCCL standard methods were followed for antibacterial activity. GC-MS was performed to identify the chemical composition of bio active fraction. Results:Among all solvent extracts, methanol extract significantly reduced the growth of S. aureus (ATCC No: 25923), methicillin resistant and methicillin sensitive S. aureus with the best zone of inhibition at 16.23, 14.06 and 15.23 mm and minimum inhibition concentration (MIC) values at 426.16, 683.22 and 512.12 µg/mL, respectively. In order to detect the active component in methanol extract, it was further purified by column chromatography, which yielded four fractions (St1, St2, St3, and St4). Among these four fractions, St3 was effective against the tested strains of S. aures, with the best zone of inhibition at 15.09, 13.25 and 14.12 mm and with best MIC values at 88.16, 128.11 and 116.12 µg/mL, respectively. Effective fraction partially purified from S. tenuifolius (St3) yielded MIC’s that were at least 20 fold less when compared to crude extract. GC-MS analysis of St3 revealed the presence of 3-[methyl-6,7-dihydro benzofuran-4 (5H)-one], 1,2-benzenedicarboxylic acid, hydroquinone, methyl ester and 3 unknown compounds. Conclusions:The study provides scientific evidence for traditional and folklore medicinal use of S. tenuifolius in skin infections treatment.

  6. Antimicrobial activities of methanolic extract of Carissa opaca roots and its fractions and compounds isolated from the most active ethyl acetate fraction

    Institute of Scientific and Technical Information of China (English)

    Dildar; Ahmed; Ramsha; Saeed; Nasir; Shakeel; Khaizran; Fatima; Aneela; Arshad

    2015-01-01

    Objective: To study the antibacterial and antifungal activities of methanolic extract of roots of Carissa opaca and its fractions in hexane, chloroform, ethyl acetate, n-butanol and water, and the isolated compounds.Methods: The zones of inhibition of the samples against test microorganisms were determined by agar well diffusion method. Minimum inhibitory concentrations of the samples were determined by agar well dilution method. Test microorganisms included four standard bacteria [Bacillus subtilis ATCC 6633(B. subtilis), Escherichia coli ATCC 8739(E. coli), Pseudomonas aeruginosa ATCC 9027(P. aeruginosa), and Staphylococcus aureus ATCC 6538], two standard fungi [Candida albicans ATCC 10231(C. albicans)] and Aspergillus niger, and six clinical isolates(B. subtilis, E. coli, P. aeruginosa, Staphylococcus aureus, Salmonella typhi and Enterobacter cloacae). The most active fraction was investigated to isolate compounds. The chemical compounds isolated from the ethyl acetate fraction were identified by gas chromatography-mass spectrometer, high performance liquid chromatography and liquid chromatography-mass spectrometer.Results: E. coli, P. aeruginosa, and C. albicans were the most susceptible. Less polar fractions exhibited stronger efficacy than polar ones, and ethyl acetate fraction proved to be the most potent. Zones of inhibition of hexane, chloroform and ethyl acetate fractions, and amoxil against C. albicans were 19.96, 22.01, 23.10 and 19.20 mm, respectively. Ethyl acetate faction was the most toxic to all the test microorganisms, with minimum inhibitory concentrations of 8.0, 7.8 and 7.78 μg/m L against P. aeruginosa, C. albicans and B. subtilis, respectively. Isolated compounds, limonene, 2’-hydroxyacetophenone, vanillin, naphthalenone, 2,3,3-trimethyl-2-(3-methylbuta-1,3-dienyl)-6-methylenecyclohexanone, 2-benzenedicarboxylic acid, mono(2-ethylhexyl) ester, β-sitosterol, vitamin E, rutin, quercetin, lupeol, epigallocatechin, showed considerable

  7. MIL-53(Fe) as a highly efficient bifunctional photocatalyst for the simultaneous reduction of Cr(VI) and oxidation of dyes

    International Nuclear Information System (INIS)

    Highlights: • Fe(III)-based MOF was firstly applied to the photocatalytic reduction reaction. • MIL-53(Fe) exhibited an outstanding photocatalytic activity for reduction of Cr(VI). • A first systematic study of the Fe(III)-based MOF as bifunctional photocatalyst. • Dyes and Cr(VI) could be also converted simultaneously over MIL-53(Fe). • MIL-53(Fe) was performed a stable and reusable visible-light-driven photocatalyst. - Abstract: A bifunctional photocatalyst-Fe-benzenedicarboxylate (MIL-53(Fe)) has been synthesized successfully via a facile solvothermal method. The resulting MIL-53(Fe) photocatalyst exhibited an excellent visible light (λ ≥ 420 nm) photocatalytic activity for the reduction of Cr(VI), the reduction rate have reached about 100% after 40 min of visible light irradiation, which has been more efficient than that of N-doped TiO2 (85%) under identical experimental conditions. Further experimental results have revealed that the photocatalytic activity of MIL-53(Fe) for the reduction of Cr(VI) can be drastically affected by the pH value of the reaction solution, the hole scavenger and atmosphere. Moreover, MIL-53(Fe) has exhibited considerable photocatalytic activity in the mixed systems (Cr(VI)/dyes). After 6 h of visible light illumination, the reduction ratio of Cr(VI) and the degradation ratio of dyes have been exceed 60% and 80%, respectively. More significantly, the synergistic effect can also be found during the process of photocatalytic treatment of Cr(VI) contained wastewater under the same photocatalytic reaction conditions, which makes it a potential candidate for environmental restoration. Finally, a possible reaction mechanism has also been investigated in detail

  8. Olsalazine-Based Metal-Organic Frameworks as Biocompatible Platforms for H[subscript 2] Adsorption and Drug Delivery

    Energy Technology Data Exchange (ETDEWEB)

    Levine, Dana J.; Run,; #269; evski, Tom; #269; e,; Kapelewski, Matthew T.; Keitz, Benjamin K.; Oktawiec, Julia; Reed, Douglas A.; Mason, Jarad A.; Jiang, Henry Z.H.; Colwell, Kristen A.; Legendre, Christina M.; FitzGerald, Stephen A.; Long, Jeffrey R. [LBNL; (Oberlin); (UCB)

    2016-09-07

    The drug olsalazine (H4olz) was employed as a ligand to synthesize a new series of mesoporous metal–organic frameworks that are expanded analogues of the well-known M2(dobdc) materials (dobdc4– = 2,5-dioxido-1,4-benzenedicarboxylate; M-MOF-74). The M2(olz) frameworks (M = Mg, Fe, Co, Ni, and Zn) exhibit high surface areas with large hexagonal pore apertures that are approximately 27 Å in diameter. Variable temperature H2 adsorption isotherms revealed strong adsorption at the open metal sites, and in situ infrared spectroscopy experiments on Mg2(olz) and Ni2(olz) were used to determine site-specific H2 binding enthalpies. In addition to its capabilities for gas sorption, the highly biocompatible Mg2(olz) framework was also evaluated as a platform for the delivery of olsalazine and other encapsulated therapeutics. The Mg2(olz) material (86 wt % olsalazine) was shown to release the therapeutic linker through dissolution of the framework under simulated physiological conditions. Furthermore, Mg2(olz) was used to encapsulate phenethylamine (PEA), a model drug for a broad class of bioactive compounds. Under simulated physiological conditions, Mg2(olz)(PEA)2 disassembled to release PEA from the pores and olsalazine from the framework itself, demonstrating that multiple therapeutic components can be delivered together at different rates. The low toxicity, high surface areas, and coordinatively unsaturated metal sites make these M2(olz) materials promising for a range of potential applications, including drug delivery in the treatment of gastrointestinal diseases.

  9. SYNTHESIS AND CRYSTAL STRUCTURE OF A NOVEL 3D Ni(Ⅱ) POLYMER VIA HYDROGEN-BONDED AND π…π STACKING:[Ni(μ-ISOPHTHALATE)(CH3OH)4]n%一个新型的通过氢键和π…π相互作用形成的三维Ni(Ⅱ)聚合物[Ni(u-isophthalate)(CH3OH)4]n

    Institute of Scientific and Technical Information of China (English)

    谢明进; 徐靖源; 阎世平

    2004-01-01

    A novel nickel (Ⅱ) complex [Ni(m-phth)(CH3OH)4]n (m-phth=isophthalate or 1, 3-benzenedicarboxylate) has been prepared and characterized. Single crystal X-ray diffraction analysis reveals that the complex crystallizes in monoclinic system, space group C2/c, a=1. 693(8)nm, b=1.296 5(6)nm,c=0.734 0(3)nm, α=90°,β=109.383(7)°.γ=76. 763(5)°,andV=1. 519 9(11)nm3, Z=4. The coordination geometry at each Ni(Ⅱ) center is a nearly perfect octahedron. Adjacent lD zigzag chains are connected by hydrogen bonds and π…π interactions to form three-dimensional network.%合成了一个新型的镍(Ⅱ)配合物[Ni(m-path)(CH3OH)4]n(m-path)为间苯二酸),并通过X-射线衍射测得其晶体结构.晶体属单斜晶系,空间群为C2/C,晶胞参数a=1.693 1(8)nm,b=1.296 5(6)nm,c=0.734 0(3)nm,α=90°,β=109.383(7)°,y=76.763(5)°,V=1.519 9(11)nm3,Z=4.相邻的一维之字链通过氢键和π…π相互作用形成三维的网状结构.

  10. Three new Ag(I) coordination architectures based on mixed ligands: Syntheses, structures and photoluminescent properties

    International Nuclear Information System (INIS)

    Three new silver (I) coordination complexes, [Ag2(1,2-bdc)(phdat)]n (1), [Ag2(NO2-bdc)(phdat)]n (2), [Ag4(nta)3(phdat)NO3]n (3) (1,2-bdc=phthalic acid dianion, NO2-bdc=5-nitro-1,3-benzenedicarboxylic acid dianion, nta=nicotinic acid anion, phdat=2,4-diamine-6-phenyl-1,3,5-triazine) have been hydrothermally synthesized by the reactions of silver nitrate and phdat with the homologous ligands 1,2-H2bdc, NO2-H2bdc, and Hnta, respectively, and characterized by single-crystal X-ray diffractions, IR spectra, elemental analyses thermogravimetric analyses (TGA). The compound 1 exhibits a chiral 3D network with cbs/CrB self-dual topological net, which contains two kinds of single helical chains. For compound 2, the 3D network is comprised of two kinds of similar 2D sheets with the topological symbol of sql-type packed in AABBAA mode by Ag–N/O weakly contacts. And compound 3 has 2D double layer architecture, consisting of the 2D plane with hcb-type topological symbol connected by Ag–O weakly coordinations. The photoluminescent properties associated with the crystal structures of three compounds have also been measured. - Graphical abstract: Three new silver(I) coordination complexes 1–3 have been synthesized and characterized by single-crystal X-ray diffractions, IR spectra, elemental analyses, thermogravimetric analyses (TGA) and photoluminescent spectra. Highlights: ► The compound 1 exhibits a novel chiral 3D network with two kinds of single helical chains. ► 3D or 2D new Ag coordination complexes. ► The photoluminescent properties have been measured

  11. GC-MS identification of chemicals in lily root exudates%百合根系分泌物的GC-MS鉴定

    Institute of Scientific and Technical Information of China (English)

    程智慧; 徐鹏

    2012-01-01

    lower than 0.20%,11 organic compounds were identified in methanol component,mainly derivatives of parabens such as 1,2-benzenedicarboxylic acid,diisooctyl ester(52.11%) and bis(2-ethylhexyl) phthalate(40.95%),and the contents of other compounds were lower than 1%.Six derivatives of parabens were identified in petroleum ether component,such as 1,2-benzenedicarboxylic acid,diisooctyl ester(88.04%),bis(2-ethylhexyl) phthalate(9.06%),and the contents of other parabens were lower than 1%.There were abundant organic compounds identified in chloroform component,totally 19 compounds included esters,aldehyde,phenol,olefin,alkane,and so on.Among them,the contents of the following compounds were over than 1%:1,2-benzenedicarboxylic acid,diisooctyl ester(39.87%),Bis(2-ethylhexyl) phthalate(39.62%),hexadecane(1.36%),2-methoxy-1-(2-nitroethenyl)-3-(phenylmethoxy)-benzene(1.22%),phenol,2,4-bis(1,1-dimethylethyl)(1.02%).The allelopathy of diethyl ether component and the ethyl acetate component were weak and the organic compounds in the two components were not further identified.【Conclusion】 The organic compounds in lily root exudates identified by GC-MS are mainly esters.The higher level compounds in all the three components are the derivatives of parabens.Also there are few aldehyde,phenol and olefin.

  12. Synthesis and characterization of d10 metal complexes with mixed 1,3-di(1H-imidazol-4-yl)benzene and multicarboxylate ligands

    International Nuclear Information System (INIS)

    Seven new coordination polymers [Zn(H2L)(mbdc)] (1), [Zn(H3L)(btc)] (2), [Zn(H2L)(Hbtc)] (3), [Zn(H2L)(Hbtc)]·H2O (4), [Zn2(H2L)(btc)(μ2-OH)] (5), [Cd(H2L)(mbdc)] (6) and [Cd3(H2L)2(btc)2(H2O)]·5H2O (7) were synthesized by reactions of the corresponding metal salt with rigid ligand 1,3-di(1H-imidazol-4-yl)benzene (H2L) and different carboxylic acids of 1,3-benzenedicarboxylic acid (H2mbdc) and benzene-1,3,5-tricarboxylic acid (H3btc), respectively. The results of X-ray crystallographic analysis indicate that complex 1 is 1D chain while 2 is a (3,3)-connected 2D network with Point (Schläfli) symbol of (4,82). Complexes 3 and 6 are 2D networks, 4 is a 3-fold interpenetrating 3D framework with Point (Schläfli) symbol of (65,8) and 5 is a (3,8)-connected 2D network with Point (Schläfli) symbol of (3,42)2(34,46,56,68,73,8), while 7 is a (3,10)-connected 3D net with Schläfli symbol of (3,4,5)2(34,48,518,612,72,8). The thermal stability and photoluminescence of the complexes were investigated. Furthermore, DFT calculations were performed for 2–4 to discuss the temperature controlled self-assembly of the complexes. - Graphical abstract: Seven new coordination polymers with multicarboxylate and rigid ditopic 4-imidazole containing ligands have been obtained and found to show different structures and topologies. - Highlights: • Metal complexes with diverse structures of 1D chain, 2D network and 3D framework. • Mixed ligands of 1,3-di(1H-imidazol-4-yl)benzene and multicarboxylate. • Photoluminescence property

  13. A series of novel metal–organic coordination polymers constructed from the new 5-(4-imidazol-1-yl-phenyl)-2H-tetrazole spacer and aromatic carboxylates: Synthesis, crystal structures, and luminescence properties

    International Nuclear Information System (INIS)

    Using bifunctional organic ligand 5-(4-imidazol-1-yl-phenyl)-2H-tetrazole (HL) and different aromatic carboxylates as secondary ligands, four novel metal-organic coordination polymers, [Zn(L)(1,4-bdc)0.5] (1), [Zn1.5(L)(2,5-pydc)] (2), [Zn(HL)(1,2,4,5-btec)0.5] (3), and [Cd(HL)(1,2,4,5-btec)0.5] (4) (1,4-bdc, 1,4-benzenedicarboxylate; 2,5-pydc, 2,5-pyridinedicarboxylate; 1,2,4,5-btec, 1,2,4,5-benzenetetracarboxylate) have been successfully synthesized and analyzed. Compound 1 features the 2D [Zn(L)]n layers built by μ3-L bridging ligands and Zn(II) ions, which are further linked by pillared 1,4-bdc2− ligands to form a 2-fold interpenetrating dmc framework. The 3D network of compound 2 can be simplified as a rare 2-nodal (3,6)-connected rtl (rutile) topology. Compound 3 possesses a 2D layer structure which is accomplished by connecting ladder-chains to L ligands. Compound 4 exhibits 2D [Cd(1,2,4,5-btec)] layers with infinite Cd–O–Cd rods and the adjacent 2D networks are further pillared by L with terminal bidentate coordination mode to generate the final 3D structure. The solid-state luminescent studies show that compounds 1–4 display intense fluorescent emissions. - Graphical abstract: Using bifunctional organic ligand 5-(4-imidazol-1-yl-phenyl)-2H-tetrazole (HL) and different aromatic carboxylates as secondary ligands, four novel metal-organic coordination polymers have been obtained. All compounds show good luminescence properties at room temperature. Display Omitted - Highlights: • Four Zn(II)/Cd(II)-MOCPs have been successfully prepared with the rigid bifunctional ligand 5-(4-imidazol -1-yl-phenyl) -2H-tetrazole and different aromatic carboxylates mixed ligands. • Compound 2 is a 2-nodal rtl (rutile) net and compound 4 is a binodal (5, 6)-connected net with yav topology. • Compounds 1-4 display intense fluorescent emissions at room temperature

  14. Mechanism and kinetics of carbon dioxide adsorption in metal organic frameworks

    International Nuclear Information System (INIS)

    Metal-organic frameworks (MOFs) are a class of porous material possessing high crystallinity, which may be specifically targeted to carbon dioxide (CO2) capture and separation in order to meet global targets associated with the reduction of CO2 emissions from industrial sources. The selectivity of MOFs for CO2 uptake over other gases (e.g. N2) may be improved through the introduction of functional groups known to interact with carbon dioxide, e.g. amines, which react with CO2 in an acid- base mechanism. The specific mechanisms and kinetics of CO2 adsorption in such materials are not widely understood, but may be elucidated using neutron diffraction techniques. We have previously employed neutron diffraction in preliminary experiments to investigate the in situ concentration-dependent behaviour of CO2 adsorption in [Ni2(dobdc)] (dobdc = 2,5-dioxido-1,4-benzenedicarboxylate) and our recently published piperazine-functionalised framework [Ni2(dobdc)(pip)0.5]. We are further expanding our repertoire of materials and types of functional groups investigated using this method; in particular, we are investigating the interaction of CO2 molecules with pendant functional groups such as sulfones, primary amines and secondary amines. The nature of these interactions may be explored using X-ray diffraction, gas sorption, gravimetric analysis using mixed gas streams and infrared spectroscopy; however, neutron diffraction presents a powerful and unique in situ technique to probe the temperature- and concentration-dependent behaviour of CO2 binding to identify intermediate binding species, fully explore the binding mode of CO2 and investigate structural effects in the adsorbate material. Mixed gas (CO2/N2) experiments will be used to explore the specificity of the host-guest behaviour in these functionalised frameworks. Based upon this data, it will be possible explore specific chemical factors contributing to selective CO2 capture, and in doing so contribute to the design of new

  15. Synthesis, crystal structures and luminescent properties of zinc(II) metal-organic frameworks constructed from terpyridyl derivative ligand

    Science.gov (United States)

    Yang, Xiao-Le; Shangguan, Yi-Qing; Hu, Huai-Ming; Xu, Bing; Wang, Bao-Cheng; Xie, Juan; Yuan, Fei; Yang, Meng-Lin; Dong, Fa-Xin; Xue, Gang-Lin

    2014-08-01

    Five zinc(II) metal-organic frameworks, [Zn3(344-pytpy)2Cl6]n·n(H2O) (1), [Zn(344-pytpy)(ox)]n (2), [Zn2(344-pytpy)(bdc)2]n·1.5n(H2O) (3), [Zn2(344-pytpy)2 (sfdb)2]n·1.5n(H2O) (4) and [Zn3(344-pytpy)2(btc)2]n·2n(H2O) (5), (344-pytpy=4‧-(3-pyridyl)-4,2‧:6‧,4″-terpyridine, H2ox=oxalic acid, H2bdc=1,4-benzenedi-carboxylic acid, H2sfdb=4,4‧-sulfonyldibenzoic acid and H3btc=1,3,5-benzene-tricarboxylic acid) have been prepared by hydrothermal reactions. Compound 1 is a 1D chain structure, in which 344-pytpy ligand links three ZnII centers through three of terminal N-donors. Compound 2 is a 4-connected 3D framework with the dia topological net and the Schläfli symbol of 66. Compound 3 displays a unusual 3-fold interpenetrating 3D coordination network which exhibits a new intriguing (3,3,4)-connected topological net with the Schläfli symbol of (4.82)(4.85)(83). Compound 4 features a two-fold interpenetrating 4-connected 2D framework with the sql topological net and the Schläfli symbol of (44.62). Compound 5 is a new self-interpenetrating (3,3,4,4)-connected topological net with the Schläfli symbol of (6.82)2(62.82.10.12)(62.83.10)2(62.8)2. The luminescence properties of 1-5 have been investigated by emission spectra and they possess great thermal stabilities which can be stable up to around 400 °C.

  16. Synthesis and structural characterization of a new open-framework zinc terephthalate Zn 3(OH) 2(bdc) 2·2DEF, with infinite Zn-( μ3-OH)-Zn chains

    Science.gov (United States)

    Loiseau, Thierry; Muguerra, Hervé; Férey, Gérard; Haouas, Mohamed; Taulelle, Francis

    2005-03-01

    A new zinc carboxylate Zn 3(OH) 2(bdc) 2·2DEF was synthesized under mild hydrothermal conditions (100 °C, 40 h) in the presence of 1,4-benzenedicarboxylic (bdc) acid, in N,N'-diethylformamide (DEF) solvent. Its structure, characterized by means of single-crystal XRD analysis, consists of connection of ZnO 2(OH) 2 tetrahedra corner-sharing with ZnO 4(OH) 2 octahedra. Two adjacent ZnO 2(OH) 2 tetrahedra have a common edge corresponding to hydroxy group, which is also linked to the octahedrally coordinated zinc atoms with a μ3 configuration. This resulting connection mode generates infinite chains running along the c-axis, and connected to each other via the bdc ligand. Three-dimensional framework is therefore formed with channels running along the c-axis, parallel to the infinite Zn-OH-Zn chains. Within the tunnels are trapped the DEF species, which interacts via hydrogen-bond to the μ3-hydroxy of the zinc chains with the terminal oxygen atom of the formamide function. Analysis by solid state NMR ( 1H and 13C) has confirmed both the presence of occluded solvent molecules within the pores and the incorporation of carboxylate moieties into the framework. The structure of Zn 3(OH) 2(bdc) 2·2DEF is closely related to those of MOF-69 series, constructed with longer organic linkers (4,4'-biphenyldicarboxylate and 2,6-naphthalenedicarboxylate). The structure is observed to loose crystallinity upon heating and removal of the occluded DEF moieties. Crystal data for [Zn 9(OH) 6(O 2C-C 6H 4-CO 2) 6]·6[(CH 3-CH 2) 2NCHO]: a=17.7374(3) Å, b=15.2605(2) Å, c=18.2635(2) Å, β=113.071(1)°, V=4548.2(1) Å3, P21/n (no. 14), Z=1, R1=0.0510, wR2=0.1302 for 11877 reflections I>2σ(I).

  17. Syntheses, Crystal Structures and Properties of Two Cd(Ⅱ) Coordination Polymers with Mixed Ligands of 2,5-Di(pyridin-4-yl)benzaldehyde and Carboxylates

    Institute of Scientific and Technical Information of China (English)

    GONG Teng-Fei; ZHU Cheng-Feng; YE Cheng-Cheng; SHENG En-Hong; LIU Bai-Zhan; CUI Yong

    2013-01-01

    A new ligand 2,5-di(pyridin-4-yl)benzaldehyde (L) was synthesized by the reaction of pyridin-4-yl-boronic acid with 2,5-dibromobenzaldehyde.Two novel CdⅡ coordination polymers,[CdL(BDC)]·DMF (1) and [CdL(BPDC)]·4H2O (2) (BDC =1,4-benzenedicarboxylate,BPDC =4,4'-biphenyldicarboxylate),have been constructed based on the mixed ligands of L and dicaboxylic acid via solvothermal synthesis,and characterized by IR,microanalysis,TGA,single and power X-ray diffraction,and their fluorescence properties were also investigated.1 crystallizes in orthorhombic space group Pcca with a =15.8236(3),b =16.0038(3),c =20.2207(3) (A),V =5120.64(16) (A)3,Z =8,Mr =633.83,Dc =1.644 g/cm3,F(000) =2528,GOOF =1.130,the final R =0.0568 and wR =0.1513 for 4108 observed reflections with I > 2σ(Ⅰ).2 crystallizes in orthorhombic space group Pbcn with a =29.1148(1),b =16.0120(6),c =16.7097(7) (A),V =7789.8(5) (A)3,Z =8,Mr =675.88,Dc =1.153 g/cm3,F(000) =2712,GOOF =1.088,the final R =0.0670 and wR =0.1805 for 6047 observed reflections with I > 2σ(Ⅰ).The dinuclear Cd2(CO2)4 unit is linked by BDC in 1 to form a 2D sheet that is further pillared by L to create a 3D metal-organic framework,which possesses a parallelogram channel with diagonal distances of~13.3 × 17.6 (A)along the b direction.2 is structurally similar to 1,but has larger diagonal distances of~14.0 × 26.7 (A) due to the elongated auxiliary ligand BPDC compared with the BDC ligand in 1.They are both thermally stable and exhibit strong photoluminescence in the visible region.

  18. Ab initio investigation on hydrogen adsorption capability in Zn and Cu-based metal organic frameworks

    Energy Technology Data Exchange (ETDEWEB)

    Tanuwijaya, V. V., E-mail: viny.veronika@gmail.com [Engineering Physics, Faculty of Industrial Technology, Institut Teknologi Bandung Jalan Ganeca 10 Gd. T.P. Rachmat, Bandung 40132 (Indonesia); Hidayat, N. N., E-mail: avantgarde.vee@gmail.com; Agusta, M. K., E-mail: kemal@fti.itb.ac.id; Dipojono, H. K., E-mail: dipojono@tf.itb.ac.id

    2015-09-30

    One of the biggest challenge in material technology for hydrogen storage application is to increase hydrogen uptake in room temperature and pressure. As a class of highly porous material, Metal-Organic Frameworks (MOF) holds great potential with its tunable structure. However, little is known about the effect of metal cluster to its hydrogen storage capability. Investigation on this matter has been carried out carefully on small cluster of Zn and Cu-based MOF using first principles method. The calculation of two distinct building units of MOFs, namely octahedral and paddle-wheel models, have been done with B3LYP density functional method using 6-31G(d,p) and LANL2DZ basis sets. From geometry optimization of Zn-based MOF linked by benzene-dicarboxylate (MOF-5), it is found that hydrogen tends to keep distance from metal cluster group and stays above benzene ring. In the other hand, hydrogen molecule prefers to stay atop of the exposed Cu atom in Cu-based MOF system linked by the same linker group (Cu-bdc). Calculated hydrogen binding enthalpies for Zn and Cu octahedral cages at ZnO{sub 3} sites are 1.64kJ/mol and 2.73kJ/mol respectively, while hydrogen binding enthalpies for Zn and Cu paddle-wheel cages calculated on top of metal atoms are found to be at 6.05kJ/mol and 6.10kJ/mol respectively. Major difference between Zn-MOF-5 and Cu-bdc hydrogen uptake performance might be caused by unsaturated metal sites present in Cu-bdc system and the influence of their geometric structures, although a small difference on binding energy in the type of transition metal used is also observed. The comparison between Zn and Cu-based MOF may contribute to a comprehensive understanding of metal clusters and the importance of selecting best transition metal for design and synthesis of metal-organic frameworks.

  19. Ab initio investigation on hydrogen adsorption capability in Zn and Cu-based metal organic frameworks

    International Nuclear Information System (INIS)

    One of the biggest challenge in material technology for hydrogen storage application is to increase hydrogen uptake in room temperature and pressure. As a class of highly porous material, Metal-Organic Frameworks (MOF) holds great potential with its tunable structure. However, little is known about the effect of metal cluster to its hydrogen storage capability. Investigation on this matter has been carried out carefully on small cluster of Zn and Cu-based MOF using first principles method. The calculation of two distinct building units of MOFs, namely octahedral and paddle-wheel models, have been done with B3LYP density functional method using 6-31G(d,p) and LANL2DZ basis sets. From geometry optimization of Zn-based MOF linked by benzene-dicarboxylate (MOF-5), it is found that hydrogen tends to keep distance from metal cluster group and stays above benzene ring. In the other hand, hydrogen molecule prefers to stay atop of the exposed Cu atom in Cu-based MOF system linked by the same linker group (Cu-bdc). Calculated hydrogen binding enthalpies for Zn and Cu octahedral cages at ZnO3 sites are 1.64kJ/mol and 2.73kJ/mol respectively, while hydrogen binding enthalpies for Zn and Cu paddle-wheel cages calculated on top of metal atoms are found to be at 6.05kJ/mol and 6.10kJ/mol respectively. Major difference between Zn-MOF-5 and Cu-bdc hydrogen uptake performance might be caused by unsaturated metal sites present in Cu-bdc system and the influence of their geometric structures, although a small difference on binding energy in the type of transition metal used is also observed. The comparison between Zn and Cu-based MOF may contribute to a comprehensive understanding of metal clusters and the importance of selecting best transition metal for design and synthesis of metal-organic frameworks

  20. Isomorphous substitution in a flexible metal-organic framework: mixed-metal, mixed-valent MIL-53 type materials.

    Science.gov (United States)

    Breeze, Matthew I; Clet, Guillaume; Campo, Betiana C; Vimont, Alexandre; Daturi, Marco; Grenèche, Jean-Marc; Dent, Andrew J; Millange, Franck; Walton, Richard I

    2013-07-15

    Mixed-metal iron-vanadium analogues of the 1,4-benzenedicarboxylate (BDC) metal-organic framework MIL-53 have been synthesized solvothermally in N,N'-dimethylformamide (DMF) from metal chlorides using initial Fe:V ratios of 2:1 and 1:1. At 200 °C and short reaction time (1 h), materials (Fe,V)(II/III)BDC(DMF(1-x)F(x)) crystallize directly, whereas the use of longer reaction times (3 days) at 170 °C yields phases of composition [(Fe,V)(III)0.5(Fe,V)0.5(II)(BDC)(OH,F)](0.5-)·0.5DMA(+) (DMA = dimethylammonium). The identity of the materials is confirmed using high-resolution powder X-ray diffraction, with refined unit cell parameters compared to known pure iron analogues of the same phases. The oxidation states of iron and vanadium in all samples are verified using X-ray absorption near edge structure (XANES) spectroscopy at the metal K-edges. This shows that in the two sets of materials each of the vanadium and the iron centers are present in both +2 and +3 oxidation states. The local environment and oxidation state of iron is confirmed by (57)Fe Mössbauer spectrometry. Infrared and Raman spectroscopies as a function of temperature allowed the conditions for removal of extra-framework species to be identified, and the evolution of μ2-hydroxyls to be monitored. Thus calcination of the mixed-valent, mixed-metal phases [(Fe,V)(III)0.5(Fe,V)0.5(II)(BDC)(OH,F)](0.5-)·0.5DMA(+) yields single-phase MIL-53-type materials, (Fe,V)(III)(BDC)(OH,F). The iron-rich, mixed-metal MIL-53 shows structural flexibility that is distinct from either the pure Fe material or the pure V material, with a thermally induced pore opening upon heating that is reversible upon cooling. In contrast, the material with a Fe:V content of 1:1 shows an irreversible expansion upon heating, akin to the pure vanadium analogue, suggesting the presence of some domains of vanadium-rich regions that can be permanently oxidized to V(IV). PMID:23815225

  1. Three tetranuclear copper(II) cluster-based complexes constructed from 4-amino-1,2,4-triazole and different aromatic carboxylates: Assembly, structures, electrochemical and magnetic properties

    International Nuclear Information System (INIS)

    Three new tetranuclear copper(II) cluster-based complexes constructed from 4-amino-1,2,4-triazole (atrz) and three types of aromatic carboxylates, [Cu4(μ3-OH)2(atrz)2(DNBA)6] (1), [Cu4(μ3-OH)2(atrz)2(1,3-BDC)3]·2H2O (2) and [Cu4(μ3-OH)2(atrz)2(SIP)2]·4H2O (3) (HDNBA=3,5-dinitrobenzoic acid, 1,3-H2BDC=1,3-benzenedicarboxylic acid and NaH2SIP=sodium 5-sulfoisophthalate), have been hydrothermally synthesized and structurally characterized. Complex 1 displays a single-molecular CuII4 cluster structure, which is further connected by the intermolecular hydrogen-bonding interactions to form a 2D supramolecular layer. In 2, there also exist tetranuclear CuII4 clusters, which are linked by the 1,3-BDC anions to give a 3D NaCl-type framework. In 3, the CuII4 clusters are connected by the carboxyl and sulfo groups of SIP anions to generate 3D (4,8)-connected framework with a (410·614·84)(45·6)2 topology. The atrz ligand conduces to the construction of tetranuclear copper(II) clusters and the carboxylates with different non-carboxyl substituent show important effects on the final structures of the title complexes. The electrochemical and magnetic properties of 1–3 have been investigated. - Graphical abstract: Three tetranuclear copper(II) cluster-based complexes based on different carboxylates have been synthesized under hydrothermal conditions. The carboxylate anions play a key role in the formation of three different structures. Highlights: ► Three new tetranuclear copper(II) cluster-based complexes have been obtained. ► The atrz conduces to the construction of tetranuclear copper(II) clusters. ► Carboxylates show important effect on the structures of title complexes. ► Magnetic properties and electrochemical behaviors have been reported.

  2. Bioactive compounds from Carissa opaca roots and xanthine oxidase and alpha-amylase inhibitory activities of their methanolic extract and its fractions in different solvents

    Directory of Open Access Journals (Sweden)

    Ramsha Saeed

    2015-01-01

    Full Text Available Background: Carissa opaca is known for its many ethnomedicinal uses. There was a need to study its bioactivities and identify its phytochemicals. Objective: The objective was to isolate and identify phytochemicals from roots of C. opaca and to evaluate xanthine oxidase (XO and alpha-amylase inhibitory activities of their methanolic extract and its fractions. Materials and Methods: Methanolic extract of finely divided powder of roots of C. opaca was obtained by cold maceration, followed by its fractionation to obtain hexane, chloroform, ethyl acetate, n-butanolic, and aqueous fractions. Phytochemicals screening was done by standard protocols. XO and alpha-amylase inhibitory activities of the methanolic extract and its fractions were studied. The most active ethyl acetate fraction was subjected to the column and thin layer chromatography to isolate its compounds, which were identified by gas chromatography-mass spectrometry and high-performance liquid chromatography comparison. Results: Methanolic extract displayed significant activity against both the enzymes with IC 50 of 156.0 mg/mL and 5.6 mg/mL for XO and alpha-amylase, respectively. Ethyl acetate fraction showed highest activity against both the enzymes with IC 50 of 129 mg/mL and 4.9 mg/mL for XO and alpha-amylase, respectively. Chloroform fraction had IC 50 of 154.2 mg/mL and 5.5 mg/mL for XO and alpha-amylase, respectively. Aqueous fraction exhibited significant efficacy against alpha-amylase (IC 50 5.0 mg/mL. Hexane fraction showed good activity against alpha-amylase in a dose-dependent manner but exhibited opposite trend against XO. The compounds isolated from ethyl acetate fraction included limonene, vanillin, lupeol, rutin, quercetin, b-sitosterol, Vitamin E, 2-hydroxyacetophenone, naphthalenone, 2,3,3-trimethyl-2-(3-methylbuta-1,3-dienyl-6-methylenecyclohexanone, and 2-benzenedicarboxylic acid, mono(2-ethylhexyl ester. Conclusions: Moderately polar phytochemicals of C. opaca roots

  3. Ab initio investigation on hydrogen adsorption capability in Zn and Cu-based metal organic frameworks

    Science.gov (United States)

    Tanuwijaya, V. V.; Hidayat, N. N.; Agusta, M. K.; Dipojono, H. K.

    2015-09-01

    One of the biggest challenge in material technology for hydrogen storage application is to increase hydrogen uptake in room temperature and pressure. As a class of highly porous material, Metal-Organic Frameworks (MOF) holds great potential with its tunable structure. However, little is known about the effect of metal cluster to its hydrogen storage capability. Investigation on this matter has been carried out carefully on small cluster of Zn and Cu-based MOF using first principles method. The calculation of two distinct building units of MOFs, namely octahedral and paddle-wheel models, have been done with B3LYP density functional method using 6-31G(d,p) and LANL2DZ basis sets. From geometry optimization of Zn-based MOF linked by benzene-dicarboxylate (MOF-5), it is found that hydrogen tends to keep distance from metal cluster group and stays above benzene ring. In the other hand, hydrogen molecule prefers to stay atop of the exposed Cu atom in Cu-based MOF system linked by the same linker group (Cu-bdc). Calculated hydrogen binding enthalpies for Zn and Cu octahedral cages at ZnO3 sites are 1.64kJ/mol and 2.73kJ/mol respectively, while hydrogen binding enthalpies for Zn and Cu paddle-wheel cages calculated on top of metal atoms are found to be at 6.05kJ/mol and 6.10kJ/mol respectively. Major difference between Zn-MOF-5 and Cu-bdc hydrogen uptake performance might be caused by unsaturated metal sites present in Cu-bdc system and the influence of their geometric structures, although a small difference on binding energy in the type of transition metal used is also observed. The comparison between Zn and Cu-based MOF may contribute to a comprehensive understanding of metal clusters and the importance of selecting best transition metal for design and synthesis of metal-organic frameworks.

  4. Influence of Agathi grandiflora active principles inhibit viral multiplication and stimulate immune system in Indian white shrimp Fenneropenaeus indicus against white spot syndrome virus infection.

    Science.gov (United States)

    Bindhu, Francis; Velmurugan, Subramanian; Donio, Mariathason Birdilla Selva; Michaelbabu, Mariavincent; Citarasu, Thavasimuthu

    2014-12-01

    Five herbs including Adathoda vasica, Agathi grandiflora, Leucas aspera, Psoralea corylifolia, and Quercus infectoria were selected to screen the antiviral and immunostimulant activity against white spot syndrome virus (WSSV) and Vibrio harveyi respectively using different organic polar and non-polar solvents. Based on the initial screening results, ethyl acetate and methanolic extracts of A. grandiflora had strong antiviral and immunostimulant activities. Those extracts incubated with WSSV injected Fenneropenaeus indicus got only 20% mortality and no PCR positive signals were seen in two step PCR amplification. The methanolic extracts of A. grandiflora were further purified through silica column chromatography and the fractions screened again for antiviral and immunostimulant activity. The secondary screening results revealed that, the fractions of F5 to F7 had effectively controlled the WSSV multiplication and V. harveyi growth. The pooled fractions (F5 to F7) was structurally characterized by gas chromatograph-mass spectrometry (GC-MS) analysis and few compounds were identified including 3,7.11,15-Tetramethyl-2-Hexane-1-ol, pytol and 1,2-Benzenedicarboxylic acid, diisooctyl ester. The pooled fractions were mixed with the basal feed ingredients at the concentration of 100 (D-1), 200 (D-2), 300 (D-3) and 400 (D-4) mg kg(-1) and the diets fed to the F. indicus (9.0 ± 0.5 g) for 30 days. After the completion of feeding trail, they were challenged with virulent WSSV and studied the cumulative mortality, molecular diagnosis by quantitative real time PCR (qRT-PCR), biochemical, haematological and immunological parameters. The control diet fed F. indicus succumbed to death 100% within 3 days whereas the D-3 and D-4 helped to reduced the cumulative mortality of 60-80% respectively. The qRT-PCR revealed that, the WSSV copy number was gradually decreased when increasing concentration of A. grandiflora extract active fraction in the diets. The diets D-3 and D-4 helped to

  5. Organic compound composition in soil and sediments collected in Jackson, Mississippi.

    Science.gov (United States)

    Gołębiowski, Marek; Stepnowski, Piotr; Hemmingway, Tometrick; Leszczyńska, Danuta

    2016-06-01

    The aim of our study was to identify organic pollutants found in soil and sediment samples collected within the Jackson, MS metropolitan area. The chemical characterization of the organic compound fractions in soil and sediment samples was carried out by separating the organic fraction using column chromatography (CC) and quantitatively analyzing the polycyclic aromatic hydrocarbons (PAHs), n-alkanes and other organic compounds using gas chromatography-electron impact mass spectrometry (GC-MS). Fifty-six compounds were identified and quantified in the soil samples and 33 compounds were identified and quantified in the sediment samples. The PAHs, n-alkanes and other organic compound profiles in the soil and sediment samples were compared. The percentage contents of the organic compounds in the soil samples were very diverse (from traces to 12.44 ± 1.47%). The compounds present in the highest concentrations were n-alkanes: n-C31 (12.44 ± 1.47%), n-C29 (11.64 ± 1.21%), and n-C33 (8.95 ± 1.08%). The components occurring in smaller quantities (from 1% to 5%) were 2 PAHs (fluoranthene 1.28 ± 0.25%, pyrene 1.16 ± 0.20%), 10 n-alkanes from n-C21 (1.25 ± 0.29%) to n-C32 (2.67 ± 0.52%) and 11 other compounds (e.g., 2-pentanol, 4-methyl (3.33 ± 0.44%), benzyl butyl phthalate (4.25 ± 0.59%), benzenedicarboxylic acid (1.14 ± 0.08%), ethane, 1,1-diethoxy (3.15 ± 0.41) and hexadecanoic acid (2.52 ± 0.34). The soil samples also contained 30 compounds present in concentrations <1% (e.g., anthracene (0.13 ± 0.04%), n-C20 (0.84 ± 0.21%) and acetic acid (0.12 ± 0.04%). The compounds present in the highest concentrations in the sediment samples were PAHs: pyrene (7.73 ± 1.15%) and fluoranthene (6.23 ± 1.07%) and n-alkanes: n-C31 (6.74 ± 1.21%), n-C29 (6.65 ± 0.98%) and n-C27 (6.13 ± 1.09%). The remaining organic compounds were present in smaller quantities (< 5%). PMID:26943144

  6. Photo- and thermochromic and adsorption properties of porous coordination polymers based on bipyridinium carboxylate ligands.

    Science.gov (United States)

    Toma, Oksana; Mercier, Nicolas; Allain, Magali; Kassiba, Abdel Adi; Bellat, Jean-Pierre; Weber, Guy; Bezverkhyy, Igor

    2015-09-21

    The zwitterionic bipyridinium carboxylate ligand 1-(4-carboxyphenyl)-4,4'-bipyridinium (hpc1) in the presence of 1,4-benzenedicarboxylate anions (BDC(2-)) and Zn(2+) ions affords three porous coordination polymers (PCPs): [Zn5(hpc1)2(BDC)4(HCO2)2]·2DMF·EtOH·H2O (1), [Zn3(hpc1)(BDC)2(HCO2)(OH)(H2O)]·DMF·EtOH·H2O (2), and [Zn10(hpc1)4(BDC)7(HCO2)2(OH)4(EtOH)2]·3DMF·3H2O (3), with the formate anions resulting from the in situ decomposition of dimethylformamide (DMF) solvent molecules. 1 and 3 are photo- and thermochromic, turning dark green as a result of the formation of bipyridinium radicals, as shown by electron paramagnetic resonance measurements. Particularly, crystals of 3 are very photosensitive, giving an eye-detectable color change upon exposure to the light of the microscope in air within 1-2 min. A very nice and interesting feature is the regular discoloration of crystals from the "edge" to the "core" upon exposition to O2 (reoxidation of organic radicals) due to the diffusion of O2 inside the pores, with this discoloration being slower in an oxygen-poor atmosphere. The formation of organic radicals is explained by an electron transfer from the oxygen atoms of the carboxylate groups to pyridinium cycles. In the structure of 3', [Zn10(hpc1)4(BDC)7(OH)6(H2O)2], resulting from the heating of sample 3 (desolvation and loss of CO molecules due to the decomposition of formate anions), no suitable donor-acceptor interaction is present, and as a consequence, this compound does not exhibit any chromic properties. The presence of permanent porosity in desolvated 1, 2, and 3' is confirmed by methanol adsorption at 25 °C with the adsorbed amount reaching 5 wt % for 1, 10 wt % for 3', and 13 wt % for 2. The incomplete desorption of methanol at 25 °C under vacuum points to strong host-guest interactions. PMID:26370743

  7. Anion-controlled assembly of metal 3,5-bis(benzimidazol-1-ylmethyl) benzoate complexes: Synthesis, characterization and property

    International Nuclear Information System (INIS)

    Hydrothermal reactions of 3,5-bis(benzimidazol-1-ylmethyl)benzoic acid (HL) with Cd(II), Cu(II) and Zn(II) salts provide eight new metal complexes which were characterized by single crystal and powder X-ray diffraction, IR, elemental and thermogravimetric analyses. Two cadmium frameworks [Cd(L)2]·2H2O (1) and [Cd(L)Cl] (2) have 3D structures with (42.65.83)(42.6) and rtl (4.62)2(42.610.83) topologies, respectively. Structural diversity of four copper complexes [Cu3(L)2]·NO3·0.5H2O (3), [Cu2(HL)2(SO4)]·3.5H2O (4), [Cu(L)(bdc)0.5]·1.5H2O (5) and [Cu2(L)(HL)(Hbdc)] (6) (H2bdc=1,4-benzenedicarboxylic acid) is achieved through the alteration of copper salts and addition of auxiliary ligand. As a result, 3 has a 1D ladder structure, 4 is a discrete dinuclear complex, 5 displays a (3,4)-connected 2-nodal 3-fold interpenetrating framework with (42.6.102.12)(42.6) topology, 6 exhibits a 4-connected uninodal 2D sql (44.62) network. Within the zinc series, ZnCl2 and ZnSO4 were used for the syntheses of [Zn(L)Cl] (7) and [Zn(L)(SO4)0.5]·2H2O (8), respectively. 7 shows a 3-connected uninodal 2D hcb network with (63) topology and 8 is a (3,6)-connected 2-nodal 3D framework with (42.6)2(44.62.88.10) topology. The luminescent properties of the Cd(II) and Zn(II) complexes were investigated. - Graphical abstract: Eight new complexes have been successfully synthesized from the hydrothermal reactions of Cd(II), Cu(II) and Zn(II) salts with 3,5-bis(benzimidazol-1-ylmethyl)benzoic acid. The complexes exhibited anion-controlled structural diversity. - Highlights: • Metal complexes have diverse structures of 1D chains, 2D networks and 3D frameworks. • Anion-controlled assembly of the complexes is reported. • The luminescent properties of the Cd(II) and Zn(II) complexes were investigated

  8. Understanding Hydrogen Sorption in In- soc -MOF: A Charged Metal-Organic Framework with Open-Metal Sites, Narrow Channels, and Counterions

    KAUST Repository

    Pham, Tony

    2015-03-04

    © 2015 American Chemical Society. Grand canonical Monte Carlo (GCMC) simulations of hydrogen sorption were performed in In-soc-MOF, a charged metal-organic framework (MOF) that contains In3O trimers coordinated to 5,5′-azobis(1,3-benzenedicarboxylate) linkers. The MOF contains nitrate counterions that are located in carcerand-like capsules of the framework. This MOF was shown to have a high hydrogen uptake at 77 K and 1.0 atm. The simulations were performed with a potential that includes explicit many-body polarization interactions, which were important for modeling gas sorption in a charged/polar MOF such as In-soc-MOF. The simulated hydrogen sorption isotherms were in good agreement with experiment in this challenging platform for modeling. The simulations predict a high initial isosteric heat of adsorption, Qst, value of about 8.5 kJ mol-1, which is in contrast to the experimental value of 6.5 kJ mol-1 for all loadings. The difference in the Qst behavior between experiment and simulation is attributed to the fact that, in experimental measurements, the sorbate molecules cannot access the isolated cages containing the nitrate ions, the most energetically favorable site in the MOF, at low pressures due to an observed diffusion barrier. In contrast, the simulations were able to capture the sorption of hydrogen onto the nitrate ions at low loading due to the equilibrium nature of GCMC simulations. The experimental Qst values were reproduced in simulation by blocking access to all of the nitrate ions in the MOF. Furthermore, at 77 K, the sorbed hydrogen molecules were reminiscent of a dense fluid in In-soc-MOF starting at approximately 5.0 atm, and this was verified by monitoring the isothermal compressibility, βT, values. The favorable sites for hydrogen sorption were identified from the polarization distribution as the nitrate ions, the In3O trimers, and the azobenzene

  9. 含1,3,4-噻二唑与苯共轭结构聚酯的合成与表征%Synthesis and characterization of polyester containing 1,3,4-thiadiazole and benzene

    Institute of Scientific and Technical Information of China (English)

    于世钧; 于明川; 王赫麟; 吴私; 刘晶; 安金成; 马百庆

    2014-01-01

    One novel compound 1 ,3-bis (2-methoxycarbonylmethylthio-1 ,3 ,4-thiadiazole )-benzene is synthesized by esterification ,hydrazidation ,cyclization and sub-stitution with 1 ,3-benzenedicarboxylic acid as starting material .A novel kind of polyester containing 1 ,3 ,4-thiadiazole is synthesized by transesterification with ethylene glycol ,1 ,3-propylene glycol and 1 ,6-hexylene glycol .The structures are confirmed by IR ,1 H NMR and MS .Polyester can be dissolved in DMF ,DMSO ,DMAC and NMP , indicating that polyester shows well solubility .Tested by GPC ,polyesters’(P1~P3) Mw are 8246、11350、7322 g/mol and PDI in the 1 .63、2 .64、1 .94 range .Tested by TG-DTA ,Polyesters’(P1~P3) 5% weight loss temperature at the 257 .89 ,260 .88 ,267 .01 ℃ .Tested by fluorescence spectroscopy monomer(4)and polyesters(P1~P3)fluorescent performance ,the results show that the monomer (4) and polyesters(P1~P3)maximum emission peaks at 361~368 nm wavelength range ,monomer(4)and polyesters(P1~P3)both emit violet fluorescence .Polyesters(P1~P3)show well solubility ,considera-ble thermal stability and fluorescent properties .%以间苯二甲酸为原料,经酯化、氨解、关环和取代四步反应合成了1,3-二(2-甲氧酰甲硫基-1,3,4-噻二唑)-苯,进一步与乙二醇、1,3-丙二醇和1,6-己二醇通过酯交换反应合成了含有1,3,4-噻二唑与苯共轭结构的聚酯(P1~P3).采用IR、1HNMR及MS对中间体和聚酯的结构进行表征.利用GPC测得聚酯P1~P3的Mw分别为11352、15350、14957g/mol,PDI分别为1.96、2.24、2.18.聚酯能溶解于DMF、DMSO、DMAC和NMP等溶剂.TG-DTA测得P1~P3的5%失重温度分别为257.89、260.88、267.01℃.化合物4和聚酯P1~P3均在361~368nm范围内发射紫光.测试结果表明,所合成聚酯具有良好的溶解性、热稳定性及荧光性能.

  10. Anion-controlled assembly of metal 3,5-bis(benzimidazol-1-ylmethyl) benzoate complexes: Synthesis, characterization and property

    Energy Technology Data Exchange (ETDEWEB)

    Kuai, Hai-Wei [Coordination Chemistry Institute, State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Nanjing National Laboratory of Microstructures, Nanjing University, Nanjing 210093 (China); Faculty of Life Science and Chemical Engineering, Huaiyin Institute of Technology, Huaian 223003 (China); Lv, Gao-Chao; Hou, Chao [Coordination Chemistry Institute, State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Nanjing National Laboratory of Microstructures, Nanjing University, Nanjing 210093 (China); Sun, Wei-Yin, E-mail: sunwy@nju.edu.cn [Coordination Chemistry Institute, State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Nanjing National Laboratory of Microstructures, Nanjing University, Nanjing 210093 (China)

    2015-03-15

    Hydrothermal reactions of 3,5-bis(benzimidazol-1-ylmethyl)benzoic acid (HL) with Cd(II), Cu(II) and Zn(II) salts provide eight new metal complexes which were characterized by single crystal and powder X-ray diffraction, IR, elemental and thermogravimetric analyses. Two cadmium frameworks [Cd(L){sub 2}]·2H{sub 2}O (1) and [Cd(L)Cl] (2) have 3D structures with (4{sup 2}.6{sup 5}.8{sup 3})(4{sup 2}.6) and rtl (4.6{sup 2}){sub 2}(4{sup 2}.6{sup 10}.8{sup 3}) topologies, respectively. Structural diversity of four copper complexes [Cu{sub 3}(L){sub 2}]·NO{sub 3}·0.5H{sub 2}O (3), [Cu{sub 2}(HL){sub 2}(SO{sub 4})]·3.5H{sub 2}O (4), [Cu(L)(bdc){sub 0.5}]·1.5H{sub 2}O (5) and [Cu{sub 2}(L)(HL)(Hbdc)] (6) (H{sub 2}bdc=1,4-benzenedicarboxylic acid) is achieved through the alteration of copper salts and addition of auxiliary ligand. As a result, 3 has a 1D ladder structure, 4 is a discrete dinuclear complex, 5 displays a (3,4)-connected 2-nodal 3-fold interpenetrating framework with (4{sup 2}.6.10{sup 2}.12)(4{sup 2}.6) topology, 6 exhibits a 4-connected uninodal 2D sql (4{sup 4}.6{sup 2}) network. Within the zinc series, ZnCl{sub 2} and ZnSO{sub 4} were used for the syntheses of [Zn(L)Cl] (7) and [Zn(L)(SO{sub 4}){sub 0.5}]·2H{sub 2}O (8), respectively. 7 shows a 3-connected uninodal 2D hcb network with (6{sup 3}) topology and 8 is a (3,6)-connected 2-nodal 3D framework with (4{sup 2}.6){sub 2}(4{sup 4}.6{sup 2}.8{sup 8}.10) topology. The luminescent properties of the Cd(II) and Zn(II) complexes were investigated. - Graphical abstract: Eight new complexes have been successfully synthesized from the hydrothermal reactions of Cd(II), Cu(II) and Zn(II) salts with 3,5-bis(benzimidazol-1-ylmethyl)benzoic acid. The complexes exhibited anion-controlled structural diversity. - Highlights: • Metal complexes have diverse structures of 1D chains, 2D networks and 3D frameworks. • Anion-controlled assembly of the complexes is reported. • The luminescent properties of the Cd

  11. Degradation of ciprofloxacin by UV/H2O2 process%UV/H2O2工艺降解环丙沙星的研究

    Institute of Scientific and Technical Information of China (English)

    袁芳; 胡春; 李礼

    2011-01-01

    The degradation of ciprofloxacin in UV/H2O2 process was investigated with a low-pressure UV lamp system.The influence of initial pH values,H2O2 concentration and water quality was discussed;the degradation products of ciprofloxacin were also analyzed.Results show that ciprofloxacin displays a pH-dependent degradation and the neutral condition is more favorable.Reaction rates increased with the increasing of H2O2 concentration,and the optimal H2O2/ciprofloxacin molar ratio at which the highest reaction rate constant is reached is 2 000.In UV direct photolysis,degradation rates of ciprofloxacin in natural water are higher than those in ultrapure water;while in UV/H2O2 process,the degradation rates in natural water are lower than those in ultrapure water.Moreover,several degradation products such as propanedioic acid,glycerin,1,4-benzenedicarboxylic acid,and some aliphatic acids etc.forming in the degradation of ciprofloxacin in UV/H2O2 process are identified by GC-MS.%采用UV/H2O2工艺去除水体中的喹诺酮类抗生素环丙沙星(CIP)。考察了溶液pH值、H2O2投加量以及水体基质对环丙沙星降解效率的影响,分析了降解产物的生成情况。研究表明,环丙沙星的降解符合拟一级反应动力学模型。降解速率受溶液pH值的影响,酸性及中性条件,有利于环丙沙星的降解。H2O2投加量的增大,使得降解速率逐渐增大,但速率增幅逐渐变缓;最佳H2O2/环丙沙星摩尔比为2 000。实际水体中存在的NOM、NO3-,促进了单独UV作用下,环丙沙星的降解。水体中的.OH焠灭剂,抑制了UV/H2O2联合作用下,环丙沙星的降解;实际水体中的光解速率常数低于超纯水中的光解速率常数。GC-MS分析表明,UV/H2O2工艺,使环丙沙星氧化降解生成氨基乙酸、丙二酸、丙三醇和对苯二甲酸等小分子有机物。