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Sample records for benzenedicarboxylic acid-ortho

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

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Zong-Hui [Key Laboratory of Macromolecular Science of Shaanxi Province, School of Chemistry & Chemical Engineering, Shaanxi Normal University, Xi’an 710062, Shaanxi Province (China); State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fsuzhou, Fujian 350002 (China); Xu, Ling, E-mail: xuling@snnu.edu.cn [Key Laboratory of Macromolecular Science of Shaanxi Province, School of Chemistry & Chemical Engineering, Shaanxi Normal University, Xi’an 710062, Shaanxi Province (China); Jiao, Huan, E-mail: jiaohuan@snnu.edu.cn [Key Laboratory of Macromolecular Science of Shaanxi Province, School of Chemistry & Chemical Engineering, Shaanxi Normal University, Xi’an 710062, Shaanxi Province (China)

    2016-06-15

    Eight kinds of 1-methyl-3-alkylimidazolium halide [RMI]X (R=ethyl (E), propyl (P), butyl (B) and amyl (A); MI = imidazolium; X= Cl{sup −}, I{sup −}) ionic liquids (ILs) were used as reaction media and obtained a series of 2D [RMI]{sub 2}[Co{sub 3}(BDC){sub 3}X{sub 2}] frameworks through the ionothermal reactions of 1,4-benzenedicarboxylic acid (H{sub 2}BDC) with Co(NO{sub 3}){sub 2}·6H{sub 2}O. The 2D [RMI]{sub 2}[Co{sub 3}(BDC){sub 3}X{sub 2}] frameworks exhibit a same (3,6) topology network with [RMI]{sup +} cations locating in the interlayer space. [RMI]{sup +} cations play a template role in the structure constructions, whose influence combining with the effect of X{sup −} anions pass to the TG behaviors. The decomposition temperatures of the [RMI]{sub 2}[Co{sub 3}(BDC){sub 3}X{sub 2}] frameworks decrease with the alkyl chains in [RMI]{sup +} cations, and the compounds containing Cl{sup −} show higher thermal stabilities than those with I{sup −}. However, compounds 1–8 exhibit two similar broad emissions at ca. 380 and 390 nm, assigned to ILCT. The RMI{sup +} templates and the X{sup −} anions do not exert their influence on the fluorescence. - Graphical abstract: Eight 2D [RMI]{sub 2}[Co{sub 3}(BDC){sub 3}X{sub 2}] compounds were synthesized through ionothermal reactions. [RMI]{sup +} cations play a template role in the structure constructions, and tune the TG behaviors combining with the effect of X{sup −} anions. Display Omitted.

  2. Syntheses, crystal structures and luminescent properties of two new 1D d 1 coordination polymers constructed from 2,2'-bibenzimidazole and 1,4-benzenedicarboxylate

    International Nuclear Information System (INIS)

    Wen Lili; Li Yizhi; Dang Dongbin; Tian Zhengfang; Ni Zhaoping; Meng Qingjin

    2005-01-01

    Two novel interesting d 1 metal coordination polymers, [Zn(H 2 bibzim)(BDC)] n (1) and [Cd(H 2 bibzim)(BDC)] n (2) [H 2 bibzim=2,2'-bibenzimidazole, BDC=1,4-benzenedicarboxylate] have been synthesized under solvothermal conditions and structurally characterized. Both 1 and 2 are constructed from infinite neutral zigzag-like one-dimensional (1D) chains. The π-π interactions and interchain hydrogen-bonding interactions further extend the 1D arrangement to generate a 3D supramolecular architecture for 1 and 2. Both complexes have high thermal stability and display strong blue fluorescent emissions in the solid state upon photo-excitation at 365 nm at room temperature. They are the first two examples that 2,2'-bibenzimidazole has been introduced into the d 1 coordination polymeric framework

  3. 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.

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

    Science.gov (United States)

    2011-02-11

    ... response to the notice of filing. III. Inert Ingredient Definition Inert ingredients are all ingredients... alcohols and hydrocarbons; surfactants such as polyoxyethylene polymers and fatty acids; carriers such as... expected to present minimal or no risk to human health or the environment. The definition of a polymer is...

  5. 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, 1,1′-methylenebis...

  6. Evaluation of a novel metal-organic framework as an adsorbent for the extraction of multiclass pesticides from coconut palm (Cocos nucifera L.): An analytical approach using matrix solid-phase dispersion and liquid chromatography.

    Science.gov (United States)

    de Jesus, Jemmyson Romário; Wanderley, Kaline Amaral; Alves Júnior, Severino; Navickiene, Sandro

    2017-08-01

    We report the synthesis, characterization, and application of [Zn(1,4-benzenedicarboxylate)(H 2 O) 2 ] n , Zn(1,4-benzenedicarboxylate) 0.99 (NH 2 -1,4-benzenedicarboxylate) 0.01 (H 2 O) 2 ] n , [Zn(1,4-benzenedicarboxylate) 0.95 (NH 2 -1,4-benzenedicarboxylate) 0.05 (H 2 O) 2 ] n , and [Zn(1,4-benzenedicarboxylate) 0.9 (NH 2 -1,4-benzenedicarboxylate) 0.1 (H 2 O) 2 ] n as sorbents for the extraction of multiclass pesticides from coconut palm. Liquid chromatography with ultraviolet diode array detection was used as the analysis technique, and the experiments were performed at one fortification level (0.1 μg/g). The recoveries were 47-67, 51-70, 58-72, and 64-76% for [Zn(1,4-benzenedicarboxylate)(H 2 O) 2 ] n , Zn(1,4-benzenedicarboxylate) 0.99 (NH 2 -1,4-benzenedicarboxylate) 0.01 (H 2 O) 2 ] n , [Zn(1,4-benzenedicarboxylate) 0.95 (NH 2 -1,4-benzenedicarboxylate) 0.05 (H 2 O) 2 ] n , and [Zn(1,4-benzenelate) 0.95 (NH 2 -1,4-benzenedicarboxylate) 0.05 (H 2 O) 2 ] n , and [Zn(1,4-benzenedicarboxylate) 0.9 (NH 2 -1,4-benzenedicarboxylate) 0.1 (H 2 O) 2 ] n , respectively, with relative standard deviation ranging from 1 to 7% (n = 3). Detection and quantification limits were 0.01-0.05 and 0.05-0.2 μg/g, respectively, for the different pesticides studied. The method developed was linear over the range tested (0.01-10.0 μg/g) with r 2  > 0.9991. A direct comparison of [Zn(1,4-benzenedicarboxylate) 0.9 (NH 2 -1,4-benzenedicarboxylate) 0.1 (H 2 O) 2 ] n with the commercially available neutral alumina showed that [Zn(1,4-benzenedicarboxylate) 0.9 (NH 2 -1,4-benzenedicarboxylate) 0.1 (H 2 O) 2 ] n was a similar extracting phase for the pesticides investigated. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Journal of Chemical Sciences | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    ]∞, exhibiting different coordination geometries · A Thirumurugan Srinivasan Natarajan · More Details Abstract Fulltext PDF. A hydrothermal reaction of a mixture of Y(NO3)3, 1,2-benzenedicarboxylic acid (1,2-BDC) and NaOH gives rise to a ...

  8. 77 FR 76029 - Certain New Chemicals; Receipt and Status Information

    Science.gov (United States)

    2012-12-26

    ...) Precursor to (S) Neodymium, & Rubber Co. polymerization butadiene iso-bu Department 100D. catalyst... 11/13/2012 2/10/2013 H.B. Fuller (G) Industrial (G) 1,4- Company. adhesive. benzenedicarboxylic acid.... Fuller (G) Industrial (G) Alkane diacid, Company. adhesive. polymer with hexanedioic acid, alkanediol...

  9. composition of non volatile oils and antimicrobial activities of ...

    African Journals Online (AJOL)

    dell

    . 3.45. 1,2-Benzenedicarboxylic acid, diisooctyl ester. -. -. -. -. -. 0.24. MDRD= Dichloromethane extract of M. discolor root bark; MDRD3.2= Second fraction of the third repeated column chromatography from the VLC fraction of dichloromethane ...

  10. A multi-functional coordination polymer coexisting spontaneous chirality resolution and weak ferromagnetism

    International Nuclear Information System (INIS)

    Li, Xiu-Hua; Zhang, Qi; Hu, Ping

    2014-01-01

    A multifunctional homochiral coordination polymer, [Co(H 2 O)(BDC)(4,4′-BPY)]∙3H 2 O (1) (H 2 BDC=1,2-benzenedicarboxylate and 4,4′-BPY=4,4′-bipyridine), has been successfully isolated from Co(II) ions and mixed ligands (1,2-benzenedicarboxylate and 4,4′-bipyridine). Complex 1, which exhibits spontaneous chirality resolution and weak ferromagnetism, is built by chiral helices interconnected via end-to-end 4,4′-BPY bridges into a two-dimensional (2D) layer structure. - Graphical abstract: A 2D cobalt coordination polymer compound showing spontaneous chirality resolution and weak ferromagnetism. - Highlights: • A new 2D cobalt mix-ligand coordination polymer complex has been synthesized. • The cobalt coordination polymer complex shows spontaneous chirality resolution in solid state. • The cobalt coordination polymer complex displays dominant and weak intrachain ferromagnetic interactions

  11. 77 FR 18752 - Benzidine-Based Chemical Substances; Di-n

    Science.gov (United States)

    2012-03-28

    ... ENVIRONMENTAL PROTECTION AGENCY 40 CFR Part 721 [EPA-HQ-OPPT-2010-0573; FRL-8865-2] RIN 2070-AJ73 Benzidine-Based Chemical Substances; Di-n-pentyl phthalate (DnPP); and Alkanes, C[ihel1][ihel2]-[ihel1... substances; a SNUR for di-n-pentyl phthalate (DnPP) (1,2-benzenedicarboxylic acid, 1,2-dipentyl ester) (CAS...

  12. Selective binding of O(2) over N(2) in a redox-active metal-organic framework with open iron(II) coordination sites

    NARCIS (Netherlands)

    Bloch, E.D.; Murray, L.J.; Queen, W.L.; Chavan, S.; Maximoff, S.N.; Bigi, J.P.; Krishna, R.; Peterson, V.K.; Grandjean, F.; Smit, B.; Long, G.J.; Bordiga, S.; Brown, C.M.; Long, J.R.

    2011-01-01

    The air-free reaction between FeCl2 and H4dobdc (dobdc4- = 2,5-dioxido-1,4-benzenedicarboxylate) in a mixture of N,N-dimethylformamide (DMF) and methanol affords Fe2(dobdc)·4DMF, a metal-organic framework adopting the MOF-74 (or CPO-27) structure type. The desolvated form of this material displays a

  13. Photoactivatable Mussel-Based Underwater Adhesive Proteins by an Expanded Genetic Code.

    Science.gov (United States)

    Hauf, Matthias; Richter, Florian; Schneider, Tobias; Faidt, Thomas; Martins, Berta M; Baumann, Tobias; Durkin, Patrick; Dobbek, Holger; Jacobs, Karin; Möglich, Andreas; Budisa, Nediljko

    2017-09-19

    Marine mussels exhibit potent underwater adhesion abilities under hostile conditions by employing 3,4-dihydroxyphenylalanine (DOPA)-rich mussel adhesive proteins (MAPs). However, their recombinant production is a major biotechnological challenge. Herein, a novel strategy based on genetic code expansion has been developed by engineering efficient aminoacyl-transfer RNA synthetases (aaRSs) for the photocaged noncanonical amino acid ortho-nitrobenzyl DOPA (ONB-DOPA). The engineered ONB-DOPARS enables in vivo production of MAP type 5 site-specifically equipped with multiple instances of ONB-DOPA to yield photocaged, spatiotemporally controlled underwater adhesives. Upon exposure to UV light, these proteins feature elevated wet adhesion properties. This concept offers new perspectives for the production of recombinant bioadhesives. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Spin dynamics simulations of topological magnon insulators: From transverse current correlation functions to the family of magnon Hall effects

    Science.gov (United States)

    Mook, Alexander; Henk, Jürgen; Mertig, Ingrid

    2016-11-01

    We demonstrate theoretically that atomistic spin dynamics simulations of topological magnon insulators (TMIs) provide access to the magnon-mediated transport of both spin and heat. The TMIs, modeled by kagome ferromagnets with Dzyaloshinskii-Moriya interaction, exhibit nonzero transverse-current correlation functions from which conductivities are derived for the entire family of magnon Hall effects. Both longitudinal and transverse conductivities are studied in dependence on temperature and on an external magnetic field. A comparison between theoretical and experimental results for Cu(1,3-benzenedicarboxylate), a recently discovered TMI, is drawn.

  15. Di-(2-Ethylhexyl Phthalate and Autism Spectrum Disorders

    Directory of Open Access Journals (Sweden)

    Chiara Testa

    2012-04-01

    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 (r s=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

  16. Uji Coba Alat Penghasil Asap Cair Skala Laboratorium dengan Bahan Pengasap Serbuk Gergaji Kayu Jati Sabrang atau Sungkai (Peronema canescens

    Directory of Open Access Journals (Sweden)

    Rodiah Nurbaya Sari

    2014-05-01

    energi yang dilepas dari pembentukan asap menjadi asap cair (- 476,45 kJ/kg asap, energi yang diserap air kondensor sebesar 2,1 kJ/kg air sehingga jumlah air bersuhu 30,4oC yang dibutuhkan untuk mengembunkan 1 kg asap menjadi asap cair dengan suhu pirolisis 316,7oC adalah sebanyak 226,88 liter. Kinerja alat adalah 6,98 g/(jam. m. Komponen dominan dalam asap cair yang dihasilkan adalah senyawa 1,2-benzenedicarboxylic acid, diethyl ester (C12H14O4 sebanyak 23,61%.

  17. A multi-functional coordination polymer coexisting spontaneous chirality resolution and weak ferromagnetism

    Energy Technology Data Exchange (ETDEWEB)

    Li, Xiu-Hua, E-mail: xhli.univ@gmail.com [College of Chemistry and Chemical Engineering, Fujian Normal University, Fuzhou, 350117 Fujian (China); Zhang, Qi [School of Life Science, Changchun Normal University, Changchun, 130032 Jilin (China); Hu, Ping [Southampton Management School, University of Southampton, Highfield, Southampton SO17 1BJ (United Kingdom)

    2014-10-15

    A multifunctional homochiral coordination polymer, [Co(H{sub 2}O)(BDC)(4,4′-BPY)]∙3H{sub 2}O (1) (H{sub 2}BDC=1,2-benzenedicarboxylate and 4,4′-BPY=4,4′-bipyridine), has been successfully isolated from Co(II) ions and mixed ligands (1,2-benzenedicarboxylate and 4,4′-bipyridine). Complex 1, which exhibits spontaneous chirality resolution and weak ferromagnetism, is built by chiral helices interconnected via end-to-end 4,4′-BPY bridges into a two-dimensional (2D) layer structure. - Graphical abstract: A 2D cobalt coordination polymer compound showing spontaneous chirality resolution and weak ferromagnetism. - Highlights: • A new 2D cobalt mix-ligand coordination polymer complex has been synthesized. • The cobalt coordination polymer complex shows spontaneous chirality resolution in solid state. • The cobalt coordination polymer complex displays dominant and weak intrachain ferromagnetic interactions.

  18. Three d10 coordination polymers assembled from 3,5-bis(imidazole-1-yl)pyridine and different polycarboxylates: Syntheses, structures and luminescence properties

    Science.gov (United States)

    Pan, Jie; Zhang, Di; Xue, Zhen-Zhen; Wei, Li; Han, Song-De; Wang, Guo-Ming

    2017-11-01

    Three novel Zn(II)/Cd(II) coordination polymers, [Cd2(bip)2(m-bdc)2(H2O)2·3H2O]n (1), [Zn2(bip)2(p-bdc)2·2.5H2O]n (2) and [Zn(bip) (p-bdc)·3H2O]n (3), where bip = 3,5-bis(imidazole-1-yl)pyridine, m-H2bdc = 1,3-benzenedicarboxylic acid, p-H2bdc = 1,4-benzenedicarboxylic acid, have been successfully synthesized under solvothermal conditions. The linkage of different ligands with Cd(II) ions in compound 1 affords a (3,5)-connected layer. Furthermore, 2D→3D parallel polycatenation occurs wherein the layers are polycatenated with the adjacent two parallel layers to form a 3D framework. In 2 and 3, the polycarboxylates act as pillars to combine the metal-bip chains, yielding the layered structures. These 2D networks are extended to the final 3D supramolecular architectures by π-π stacking interactions. The results show that bip can act as a versatile building block for the construction of various coordination polymers. Moreover, the fluorescent properties of 1-3 in the solid state at room temperature have been investigated.

  19. [Chemical constituents from water extract of Radix isatidis].

    Science.gov (United States)

    He, Li-Wei; Li, Xiang; Chen, Jian-Wei; Sun, Dong-Dong; Jü, Wen-Zheng; Wang, Kang-Cai

    2006-12-01

    To study the chemical constituents from water extract of Radix isatidis. (Isatis indigotica Fort. ). The water extract was underwent absorption by D101 macroporous resin, the portion eluted by ethanol of different concentrations was isolated and purified on silica gel column repeatedly. The obtained compounds were identified and structurally elucidated by their physico-chemical properties and spectral analysis. Five compounds were isolated from water extract of Radix isatidis, and were partly identified separately: 3-[2'-(5'-hydroxymethyl) furyl] -1 (2H) -isoquinolinone-7-O-beta-D-glucoside (I), lariciresinol-4,4'-di-O-beta-D-glucopyranoside (II), lariciresinol-4-O-beta-D-glucopyranoside (III), 2-hydroxy-1, 4-benzenedicarboxylic acid (IV), mannitol (V). Compound I is a new compound and compounds IV and V were isolated from the plant for the first time.

  20. Polyaniline-intercalated MIL-101: selective CO2 sorption and super-capacitor properties

    International Nuclear Information System (INIS)

    Sokhrab B Aliev; Evgeny A Maksimovskiy; Ekaterina O Fedorovskaya; Denis G Samsonenko; Sergey A Sapchenko; Vladimir P Fedin

    2016-01-01

    A novel nano-structured hybrid material PANI(at)MIL-101(Cr) (PANI = Polyaniline, MIL-101(Cr) - tri-chromium oxo-1,4-benzenedicarboxylate) was obtained by the intra-pore oxidative polymerization of guest aniline molecules within MIL-101. The compound was fully characterized using PXRD, TGA, FT-IR spectroscopy, XPS and SEM techniques. An introduction of PANI has dramatically increased the material's selectivity towards carbon dioxide over nitrogen with a CO 2 uptake value of 2.26 mmol.g -1 at 273 K (1.2 bar). Furthermore, cyclic voltammetry measurements revealed that PANI(at)MIL-101(Cr) is a super-capacitor with a relatively high specific capacitance value of 135 F.g -1 . (authors)

  1. Improved synthesis and hydrogen storage of a microporous metal-organic framework material

    International Nuclear Information System (INIS)

    Cheng Shaojuan; Liu Shaobing; Zhao Qiang; Li Jinping

    2009-01-01

    A microporous metal-organic framework MOF-5 [Zn 4 O(BDC) 3 , BDC = 1,4-benzenedicarboxylic] was synthesized with and without H 2 O 2 by improved methods based on the previous studies. The obtained materials were characterized by X-ray diffraction, scanning electron microscopy and nitrogen adsorption, and their hydrogen storage capacities were measured. The synthesis experiments showed that H 2 O 2 favored the growth of high quality sample, large pore volume and high specific surface area. The measurements of hydrogen storage indicated that the sample with higher specific surface area and large pore volume showed better hydrogen storage behavior than other samples. It was suggested that specific surface area and pore volume influenced the capacity of hydrogen storage for MOF-5 material.

  2. Rational Design of Coordination Polymers with Flexible Oxyethylene Side Chains

    International Nuclear Information System (INIS)

    Choi, Eun Young; Gao, Chunji; Lee, Suck Hyun; Kwon, O Pil

    2012-01-01

    We rationally designed and synthesized metallopolymers with organic 1,4-benzenedicarboxylic acid (BDC) linkers with different lengths of oxyethylene side chains in order to examine the influence of side chains on the coordination characteristics. While in a previous report the BDC linkers with alkyl side chains were found to form three-dimensional (3D) isoreticular metal-organic framework (IRMOF) structures or one-dimensional (1D) coordination polymeric structures with short -O(CH 2 ) 6 CH 3 or long -O(CH 2 ) 9 CH 3 side chains, respectively, new BDC linkers with oxyethylene side chains of the same lengths, -(OCH 2 CH 2 ) 2 CH 3 and -(OCH 2 CH 2 ) 3 CH 3 , form only 3D IRMOF structures. This result is attributed to the higher flexibility and smaller volume of oxyethylene side chains compared to alkyl side chains

  3. Incorporation of Pyrazine and Bipyridine Linkers with High-Spin Fe(II) and Co(II) in a Metal–Organic Framework

    Energy Technology Data Exchange (ETDEWEB)

    Kawamura, Airi; Greenwood, Arin R.; Filatov, Alexander S.; Gallagher, Audrey T.; Galli, Giulia; Anderson, John S.

    2017-02-27

    A series of isoreticular metal organic frameworks (MOFs) of the formula M(BDC)(L) (M = Fe(II) or Co(II), BDC = 1,4-benzenedicarboxylate, L = pyrazine (pyz) or 4,4'-bipyridine (bipy)) has been synthesized and characterized by N-2 gas uptake Measurements, single crystal and powder X-ray diffraction, magnetometry, X-ray absorption spectroscopy, and Mossbauer spectroscopy. These studies indicate the formation of a permanently porous solid with high-spin Fe(II) and Co(II) centers that are weakly coupled, consistent with first-principles density functional theory calculations. This family of materials represents unusual examples of paramagnetic metal centers coordinated by linkers capable of mediating magnetic or electronic coupling in a porous framework. While only weak interactions are observed, the rigid 3D framework of the MOF dramatically impacts the properties of these materials when compared with close structural analogues.

  4. Hydrocarbon separations in a metal-organic framework with open iron(II) coordination sites.

    Science.gov (United States)

    Bloch, Eric D; Queen, Wendy L; Krishna, Rajamani; Zadrozny, Joseph M; Brown, Craig M; Long, Jeffrey R

    2012-03-30

    The energy costs associated with large-scale industrial separation of light hydrocarbons by cryogenic distillation could potentially be lowered through development of selective solid adsorbents that operate at higher temperatures. Here, the metal-organic framework Fe(2)(dobdc) (dobdc(4-) : 2,5-dioxido-1,4-benzenedicarboxylate) is demonstrated to exhibit excellent performance characteristics for separation of ethylene/ethane and propylene/propane mixtures at 318 kelvin. Breakthrough data obtained for these mixtures provide experimental validation of simulations, which in turn predict high selectivities and capacities of this material for the fractionation of methane/ethane/ethylene/acetylene mixtures, removal of acetylene impurities from ethylene, and membrane-based olefin/paraffin separations. Neutron powder diffraction data confirm a side-on coordination of acetylene, ethylene, and propylene at the iron(II) centers, while also providing solid-state structural characterization of the much weaker interactions of ethane and propane with the metal.

  5. 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

  6. 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)

    Wang, Hou; Yuan, Xingzhong; Wu, Yan; Zeng, Guangming; Chen, Xiaohong; Leng, Lijian; Wu, Zhibin; Jiang, Longbo; Li, Hui

    2015-01-01

    Highlights: • NH 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 3+ –Ti 4+ intervalence electron transfer is important for Cr(VI) reduction. • Used NH 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 2 -MIL-125(Ti)) were successfully synthesized via a facile solvothermal method. The MIL-125(Ti) and NH 2 -MIL-125(Ti) were well characterized by XRD, SEM, XPS, N 2 adsorption–desorption measurements, thermogravimetric analysis and UV–vis diffuse reflectance spectra (DRS). It is revealed that the NH 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 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 3+ –Ti 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

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

    Directory of Open Access Journals (Sweden)

    René Miranda

    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.

  8. New CE-ESI-MS analytical method for the separation, identification and quantification of seven phenolic acids including three isomer compounds in virgin olive oil.

    Science.gov (United States)

    Nevado, Juan José Berzas; Peñalvo, Gregorio Castañeda; Robledo, Virginia Rodríguez; Martínez, Gabriela Vargas

    2009-10-15

    A sensitive and expeditious CE-ESI-MS analytical method for the separation, identification and determination of seven selected antioxidants (cinnamic and benzoic acids), including three isomers of coumaric acid (ortho-, meta- and para-) has been developed. In order to obtain the analytical separation, capillary electrophoresis and CE-MS interface parameters (e.g., buffer pH and composition, sheath liquid and gas flow rates, sheath liquid composition, electrospray voltage, etc.) were carefully optimized. The polar fraction containing the selected phenolic acids was obtained using a previously optimized SPE pretreatment. An MS detector in order to extract structural information about the target compounds and facilitate their qualitative analysis was used in the negative ion mode. The proposed off-line SPE CE-ESI-MS method was validated by assessing its precision, LODs and LOQs, linearity range and accuracy. The optimized and validated method was used in order to quantify the selected antioxidants in various samples of virgin olive oil and extra-virgin olive oil obtained from the main olive varieties cropped in Castilla-La Mancha, Spain. Salicylic acid was used as internal standard throughout in order to ensure reproducibility in the quantitative analysis of the oil samples. The results confirmed the presence of hydroxyphenyl acetic, p-coumaric, ferulic and vanillic acids in substantial amounts (microg g(-1) level) in all samples.

  9. 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.

  10. Carboxylate ligands induced structural diversity of zinc(II) coordination polymers based on 3,6-bis(imidazol-1-yl)carbazole: Syntheses, structures and photocatalytic properties

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, Hong-Jian, E-mail: hjcheng@cslg.cn; Tang, Hui-Xiang; Shen, Ya-Li; Xia, Nan-Nan; Yin, Wen-Yu; Zhu, Wei; Tang, Xiao-Yan; Ma, Yun-Sheng; Yuan, Rong-Xin, E-mail: yuanrx@cslg.edu.cn

    2015-12-15

    Solvothermal reactions of Zn(NO{sub 3}){sub 2}·6H{sub 2}O with 3,6-bis(1-imidazolyl)carbazole (3,6-bmcz) and 1,4-benzenedicarboxylic acid (1,4-H{sub 2}bdc), p-phenylenediacetic acid (p-H{sub 2}pda), benzophenone-4,4-dicarboxylic acid (H{sub 2}bpda) afforded three coordination polymers [Zn(1,4-bdc)(3,6-bmcz)]{sub n} (1), {[Zn(p-pda)(3,6-bmcz)]·1.5H_2O}{sub n} (2) and {[Zn(bpda)(3,6-bmcz)]·0.25H_2O}{sub n} (3). Complexes 1–3 were characterized by elemental analysis, IR, powder X-ray diffraction, and single-crystal X-ray diffraction. Complex 1 shows 3D structure with 2D nets inclined polycatenation. Complexes 2 and 3 possess an extended 3D supramolecular architecture based on their respective 2D layers through hydrogen-bonding interactions and the π···π stacking interactions. The solid state luminescent and optical properties of 1–3 at ambient temperature were also investigated. A comparative study on their photocatalytic activity toward the degradation of methylene blue in polluted water was explored. - Graphical abstract: Reactions of Zn(NO{sub 3}){sub 2} and 3,6-(1-imidazolyl)carbazole with 1,4-benzenedicarboxylic acid, p-phenylenediacetic acid or benzophenone-4,4-dicarboxylic acid afforded three coordination polymers with different topologies and photocatalytic activity. - Highlights: • Reactions of 1,4-H{sub 2}bdc, p-H{sub 2}pda or H{sub 2}bpda with 3,6-bmcz and Zn(II) gave three CPs. • Complex 1 is a 3D entanglement. • Complex 2 or 3 is a 3D supramolecular structure based on different 2D layers. • Complex 2 exhibited good catalytic activity of methylene blue photodegradation.

  11. Anti-quorum Sensing and Anti-biofilm Activity ofDelftia tsuruhatensisExtract by Attenuating the Quorum Sensing-Controlled Virulence Factor Production inPseudomonas aeruginosa.

    Science.gov (United States)

    Singh, Vijay K; Mishra, Avinash; Jha, Bhavanath

    2017-01-01

    Multidrug-resistance bacteria commonly use cell-to-cell communication that leads to biofilm formation as one of the mechanisms for developing resistance. Quorum sensing inhibition (QSI) is an effective approach for the prevention of biofilm formation. A Gram-negative bacterium, Delftia tsuruhatensis SJ01, was isolated from the rhizosphere of a species of sedge ( Cyperus laevigatus ) grown along the coastal-saline area. The isolate SJ01 culture and bacterial crude extract showed QSI activity in the biosensor plate containing the reference strain Chromobacterium violaceum CV026. A decrease in the violacein production of approximately 98% was detected with the reference strain C. violaceum CV026. The bacterial extract (strain SJ01) exhibited anti-quorum sensing activity and inhibited the biofilm formation of clinical isolates wild-type Pseudomonas aeruginosa PAO1 and P. aeruginosa PAH. A non-toxic effect of the bacterial extract (SJ01) was detected on the cell growth of the reference strains as P. aeruginosa viable cells were present within the biofilm. It is hypothesized that the extract (SJ01) may change the topography of the biofilm and thus prevent bacterial adherence on the biofilm surface. The extract also inhibits the motility, virulence factors (pyocyanin and rhamnolipid) and activity (elastase and protease) in P. aeruginosa treated with SJ01 extract. The potential active compound present was identified as 1,2-benzenedicarboxylic acid, diisooctyl ester. Microarray and transcript expression analysis unveiled differential expression of quorum sensing regulatory genes. The key regulatory genes, LasI, LasR, RhlI , and RhlR were down-regulated in the P. aeruginosa analyzed by quantitative RT-PCR. A hypothetical model was generated of the transcriptional regulatory mechanism inferred in P. aeruginosa for quorum sensing, which will provide useful insight to develop preventive strategies against the biofilm formation. The potential active compound identified, 1

  12. Uraemic toxins induce proximal tubular injury via organic anion transporter 1-mediated uptake

    Science.gov (United States)

    Motojima, Masaru; Hosokawa, Atsuko; Yamato, Hideyuki; Muraki, Takamura; Yoshioka, Toshimasa

    2002-01-01

    A direct effect of uraemic toxins in promoting progression of chronic renal disease has not been established. In this study, we investigated the toxic effects of organic anions which characteristically appeared in the patients with progressive renal disease on renal proximal tubular cells expressing human organic anion transporter (hOAT) 1. A renal proximal tubular cell line, opossum kidney (OK) cells, was transformed with hOAT1. Among the organic anions examined, hippuric acid, para-hydroxyhippuric acid, ortho-hydroxyhippuric acid, indoxyl sulphate and indoleacetic acid showed a high affinity for hOAT1 expressed in the OK cells. Indoxyl sulphate and indoleacetic acid concentration-dependently inhibited proliferation of the hOAT1-transformed cells. The h.p.l.c. analysis demonstrated that cellular uptake of these organic anions was significantly elevated in hOAT1-transformed cells. These organic anions also concentration-dependently stimulated cellular free radical production. The degrees of inhibition of cell proliferation and the stimulation of free radical production induced by the organic anions were significantly higher in the hOAT1-transformed cells than vector-transformed cells. The stimulatory effect of indoxyl sulphate on free radical production was abolished by anti-oxidants and probenecid. Less free radical production was observed in the hOAT1-transformed cells treated with p-hydroxyhippuric acid, o-hydroxyhippuric acid compared with indoxyl sulphate and indoleacetic acid. Hippuric acid had little effect on free radical production. Organic anions present in the serum of patients with progressive renal disease may cause proximal tubular injury via hOAT1-mediated uptake. The mechanism of cellular toxicity by these uraemic toxins involves free radical production. Thus, some uraemic toxins may directly promote progression of chronic renal disease. PMID:11815391

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

    International Nuclear Information System (INIS)

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

    2014-01-01

    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. -- 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

  14. Mechanochemical solvent-free in situ synthesis of drug-loaded {Cu2(1,4-bdc)2(dabco)}n MOFs for controlled drug delivery

    Science.gov (United States)

    Nadizadeh, Zahra; Naimi-Jamal, M. Reza; Panahi, Leila

    2018-03-01

    In the present study, ibuprofen-loaded nano metal-organic frameworks (NMOFs) {Cu2(1,4-bdc)2(dabco)}n and {Cu2(1,4-bdc-NH2)2(dabco)}n (bdc=benzenedicarboxylic acid, and dabco=diazabicyclooctane) were synthesized by ball-milling at room temperature in 2 h. The produced drug-loaded Cu-NMOFs were studied as ibuprofen drug delivery system and exhibited well-defined drug release behavior, exceptionally high drug loading capacities and the ability to entrap the model drug. The loading efficiency for ibuprofen was determined about 50.54% and 50.27%, respectively. The drug release of NMOFs was also monitored, and all of the loaded drug was released in 1 day. The NMOFs were characterized by FT-IR spectroscopy, X-ray powder diffraction (XRPD), thermogravimetric analysis (TGA), SEM (scanning electron microscopy), transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDS), inductively coupled plasma (ICP), UV-vis spectroscopy and N2 adsorption porosimetry (BET&BJH).

  15. Four thiophene-pyridyl-amide-based ZnII/CdII coordination polymers: Assembly, structures, photocatalytic properties and fluorescent recognition for Fe3+

    Science.gov (United States)

    Wang, Xiu-Li; Wu, Xiao-Mei; Liu, Guo-Cheng; Li, Qiao-Min; Lin, Hong-Yan; Wang, Xiang

    2017-05-01

    By tuning metal ions and combining with different dicarboxylates, four new semi-rigid thiophene-bis-pyridyl-bis-amide-based coordination polymers, namely, [Zn(3-bptpa)(1,3-BDC)]·DMA·2H2O (1), [Zn(3-bptpa)(5-MIP)] (2), [Cd(3-bptpa)(1,3-BDC)]·2H2O (3) and [Cd(3-bptpa)(5-MIP)]·4H2O (4) (3-bptpa=N,N‧-bis(pyridine-3-yl)thiophene-2,5-dicarboxamide, 1,3-H2BDC=1,3-benzenedicarboxylic acid, 5-H2MIP=5-methylisophthalic acid, DMA=N,N-dimethylacetamide), were solvothermally/hydrothermally synthesized and structurally characterized by single-crystal X-ray diffraction analyses, IR spectra, UV-vis diffuse-reflectance spectra (DRS), powder X-ray diffraction (PXRD) and thermal gravimetric analyses (TG). The structural analysis reveals that Zn-complexes 1 and 2 are similar 2D networks. While Cd-complexes 3 and 4 exhibit similar 2-fold interpenetrating 3D α-Po frameworks with the (412·63) topology. The photocatalytic properties for the degradation of methylene blue (MB) under ultraviolet light irradiation of the title complexes have been investigated in detail. Furthermore, the luminescent sensing behaviors for metal cations of 1-4 have been studied, the results indicate that 3 is an excellent fluorescent probe, with high sensitivity, selectivity, and simple regeneration, for environmentally relevant Fe3+ ions.

  16. Phytochemical Profile of Erythrina variegata by Using High-Performance Liquid Chromatography and Gas Chromatography-Mass Spectroscopy Analyses.

    Science.gov (United States)

    Muthukrishnan, Suriyavathana; Palanisamy, Subha; Subramanian, Senthilkumar; Selvaraj, Sumathi; Mari, Kavitha Rani; Kuppulingam, Ramalingam

    2016-08-01

    Natural products derived from plant sources have been utilized to treat patients with numerous diseases. The phytochemical constituents present in ethanolic leaf extract of Erythrina variegata (ELEV) were identified by using high-performance liquid chromatography (HPLC) and gas chromatography-mass spectroscopy (GC-MS) analyses. Shade dried leaves were powdered and extracted with ethanol for analyses through HPLC to identify selected flavonoids and through GC-MS to identify other molecules. The HPLC analysis of ELEV showed the presence of gallic and caffeic acids as the major components at concentrations of 2.0 ppm and 0.1 ppm, respectively, as well as other components. GC-MS analysis revealed the presence of 3-eicosyne; 3,7,11,15-tetramethyl-2-hexadecen-1-ol; butanoic acid, 3-methyl-3,7-dimethyl-6-octenyl ester; phytol; 1,2-benzenedicarboxylic acid, diundecyl ester; 1-octanol, 2-butyl-; squalene; and 2H-pyran, 2-(7-heptadecynyloxy) tetrahydro-derivative. Because pharmacopuncture is a new evolving natural mode that uses herbal extracts for treating patients with various ailments with minimum pain and maximum effect, the results of this study are particularly important and show that ELEV possesses a wide range of phytochemical constituents, as indicated above, as effective active principle molecules that can be used individually or in combination to treat patients with various diseases. Copyright © 2016. Published by Elsevier B.V.

  17. Interactions on External MOF Surfaces: Desorption of Water and Ethanol from CuBDC Nanosheets.

    Science.gov (United States)

    Elder, Alexander C; Aleksandrov, Alexandr B; Nair, Sankar; Orlando, Thomas M

    2017-10-03

    The external surfaces of metal-organic framework (MOF) materials are difficult to experimentally isolate due to the high porosities of these materials. MOF surface surrogates in the form of copper benzenedicarboxylate (CuBDC) nanosheets were synthesized using a bottom-up approach, and the surface interactions of water and ethanol were investigated by temperature-programmed desorption (TPD). A method of analysis of diffusion-influenced TPD was developed to measure the desorption properties of these porous materials. This approach also allows the extraction of diffusion coefficients from TPD data. The transmission Fourier transform infrared spectra, powder X-ray diffraction patterns, and TPD data indicate that water desorbs from CuBDC nanosheets with activation energies of 44 ± 2 kJ/mol at edge sites and 58 ± 1 kJ/mol at external surface and internal and pore sites. Ethanol desorbs with activation energies of 58 ± 1 kJ/mol at internal pore sites and 66 ± 0.4 kJ/mol at external surface sites. Co-adsorption of water and ethanol was also investigated. The presence of ethanol was found to inhibit the desorption of water, resulting in a water desorption process with an activation energy of 68 ± 0.7 kJ/mol.

  18. Improved resolution and simplification of the spin-diffusion-based NMR method for the structural analysis of mixed-linker MOFs

    Science.gov (United States)

    Krajnc, Andraž; Bueken, Bart; De Vos, Dirk; Mali, Gregor

    2017-06-01

    Nuclear magnetic resonance spectroscopy combined with modeling represents a powerful tool for the structural analysis of heterogeneous materials. In this contribution we describe an upgraded method, particularly suited for the structural analysis of mixed-linker metal-organic framework materials, which is based on the measurement and modeling of proton spin diffusion among constituents. We tested the method on a UiO-66-type metal-organic material, in which the organic building units were 1,4-benzenedicarboxylate and trans-1,4-cyclohexanedicarboxylate anions distributed within the framework in an unknown manner. We showed that resolution of the signals of different building units could be significantly enhanced by the carbon-detected version of the proton spin-diffusion measurement. Because this kind of measurement is much more time consuming than the proton-detected measurement and because one has to carry out several two-dimensional measurements to extract spin-diffusion curves, we inspected the possibility of reducing the number of such measurements. This could be done by limiting the analysis to short mixing times, for which, as shown in this contribution, linear approximation is valid. When working in the linear regime, only a few experimental points are needed to determine the slope of spin-diffusion curves. Usage of short spin-diffusion mixing times significantly shortened the total measurement time and also markedly simplified the modeling of spin-diffusion curves.

  19. Important nutritional constituents, flavour components, antioxidant and antibacterial properties of Pleurotus sajor-caju.

    Science.gov (United States)

    Gogavekar, Shweta S; Rokade, Shilpa A; Ranveer, Rahul C; Ghosh, Jai S; Kalyani, Dayanand C; Sahoo, Akshaya K

    2014-08-01

    Oyster mushroom (Pleurotus sajor-caju) cultivated in the laboratory was studied for nutritional constituents, flavor components, antioxidant and antibacterial properties. Nutritional constituents estimated per 100 g dry weight (d.w.) include protein (29.3 g), carbohydrate (62.97 g), crude fat (0.91 g), ash (6.82 g) and crude fiber (12.3 g). Energy value of this mushroom was about 297.5 kcal/100 g d.w. Major mineral components estimated include Ca, Fe, and Mg with highest level of 505.0, 109.5 and 108.7 mg/100 g respectively. Methanolic extract containing significant amounts of phenols and flavonoids showed free radical scavenging potential and antibacterial activities against various spp. of Gram positive and Gram negative bacteria. Compounds responsible for antibacterial activities analyzed by GC-MS include β- Sistosterol, Cholestanol, 1,5-Dibenzoylnaphthalene and 1,2-Benzenedicarboxylic acid. Flavor components extracted by hot extraction method were found to be higher in number and concentration than the cold extraction method. The characteristic flavor component of mushroom i.e. 1-Octen-3-ol was better extracted by hot than the cold.

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

    Directory of Open Access Journals (Sweden)

    Adriana Idalina Torcato de Oliveira

    2016-01-01

    Full Text Available 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.

  1. 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.

  2. Crystal structures and luminescence of two cadmium-carboxylate cluster-based compounds with mixed ligands

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Hui-Fang; Lei, Qian; Wang, Yu-Ling; Yin, Shun-Gao; Liu, Qing-Yan [College of Chemistry and Chemical Engineering and Key Lab. of Functional Small Organic Molecule of Ministry of Education, Jiangxi Normal Univ., Nanchang (China)

    2017-04-04

    Reactions of Cd(NO{sub 3}){sub 2}.4H{sub 2}O with 2-quinolinecarboxylic acid (H-QLC) in the presence of 1,4-benzenedicarboxylic acid (H{sub 2}-BDC) or 1,3,5-benzenetricarboxylic acid (H-BTC) in DMF/H{sub 2}O solvent afforded two compounds, namely, [Cd(QLC)(BDC){sub 1/2}(H{sub 2}O)]{sub n} (1) and [Cd(QLC)(BTC){sub 1/3}]{sub n} (2). Both compounds are two-dimensional (2D) frameworks but feature different cadmium-carboxylate clusters as a result of the presence of the polycarboxylate ligands with different geometries and coordination preference. The dinuclear Cd{sub 2}(QLC){sub 2} units in 1 are bridged by the pairs of bridging water ligands to give a one-dimensional (1D) chain, which is further linked by the second ligand of BDC{sup 2-} to form a 2D structure. Compound 2 is constructed from unique hexanuclear macrometallacyclic Cd{sub 6}(QLC){sub 6} clusters, which are linked by the surrounding BTC{sup 3-} ligands to generate a 2D structure. Photoluminescence studies showed both compounds exhibit ligand-centered luminescent emissions with emission maxima at 405 and 401 nm, respectively. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  3. Carboxylate ligands induced structural diversity of zinc(II) coordination polymers based on 3,6-bis(imidazol-1-yl)carbazole: Syntheses, structures and photocatalytic properties

    Science.gov (United States)

    Cheng, Hong-Jian; Tang, Hui-Xiang; Shen, Ya-Li; Xia, Nan-Nan; Yin, Wen-Yu; Zhu, Wei; Tang, Xiao-Yan; Ma, Yun-Sheng; Yuan, Rong-Xin

    2015-12-01

    Solvothermal reactions of Zn(NO3)2·6H2O with 3,6-bis(1-imidazolyl)carbazole (3,6-bmcz) and 1,4-benzenedicarboxylic acid (1,4-H2bdc), p-phenylenediacetic acid (p-H2pda), benzophenone-4,4-dicarboxylic acid (H2bpda) afforded three coordination polymers [Zn(1,4-bdc)(3,6-bmcz)]n (1), {[Zn(p-pda)(3,6-bmcz)]·1.5H2O}n (2) and {[Zn(bpda)(3,6-bmcz)]·0.25H2O}n (3). Complexes 1-3 were characterized by elemental analysis, IR, powder X-ray diffraction, and single-crystal X-ray diffraction. Complex 1 shows 3D structure with 2D nets inclined polycatenation. Complexes 2 and 3 possess an extended 3D supramolecular architecture based on their respective 2D layers through hydrogen-bonding interactions and the π···π stacking interactions. The solid state luminescent and optical properties of 1-3 at ambient temperature were also investigated. A comparative study on their photocatalytic activity toward the degradation of methylene blue in polluted water was explored.

  4. Analysis of chemical signatures of alkaliphiles using fatty acid methyl ester analysis

    Directory of Open Access Journals (Sweden)

    Basha Sreenivasulu

    2017-01-01

    Full Text Available Background: Fatty acids occur in nearly all living organisms as the important predominant constituents of lipids. While all fatty acids have essentially the same chemical nature, they are an extremely diverse group of compounds. Materials and Methods: To test the hypothesis, fatty acids of alkaliphiles isolates, Bacillus subtilis SVUNM4, Bacillus licheniformis SVUNM8, Bacillus methylotrohicus SVUNM9, and Paenibacillus dendritiformis SVUNM11, were characterized compared using gas chromatography-mass spectrometry (GC-MS analysis. Results: The content of investigated ten fatty acids, 1, 2-benzenedicarboxylic acid butyl 2-methylpropyl ester, phthalic acid, isobutyl 2-pentyl ester, dibutyl phthalate, cyclotrisiloxane, hexamethyl, cyclotetrasiloxane, octamethyl, dodecamethyl, heptasiloxane 1,1,3,3,5,5,7,7,9,9,11,11,13,13-etradecamethyl, 7,15-dihydroxydehydroabietic acid, methyl ester, di (trimethylsilyl ether, hentriacontane, 2-thiopheneacetic acid, undec-2-enyl ester, obviously varied among four species, suggesting each species has its own fatty acid pattern. Conclusions: These findings demonstrated that GC-MS-based fatty acid profiling analysis provides the reliable platform to classify these four species, which is helpful for ensuring their biotechnological interest and novel chemotaxonomic.

  5. A series of novel lanthanide carboxyphosphonates with a 3D framework structure: synthesis, structure, and luminescent and magnetic properties.

    Science.gov (United States)

    Chen, Kai; Dong, Da-Peng; Sun, Zhen-Gang; Jiao, Cheng-Qi; Li, Chao; Wang, Cheng-Lin; Zhu, Yan-Yu; Zhao, Yan; Zhu, Jiang; Sun, Shou-Hui; Zheng, Ming-Jing; Tian, Hui; Chu, Wei

    2012-08-28

    By introduction of 1,4-benzenedicarboxylic acid as the second organic ligand, a series of novel lanthanide carboxyphosphonates with a 3D framework structure, namely, [Ln(3)(H(2)L)(HL)(2)(bdc)(2)(H(2)O)]·7H(2)O (Ln = La (1), Ce (2), Pr (3), Nd (4), Sm (5), Eu (6), Gd (7), Tb (8); H(3)L = H(2)O(3)PCH(2)NC(5)H(9)COOH; H(2)bdc = HOOCC(6)H(4)COOH) have been synthesized under hydrothermal conditions. Compounds are isostructural and feature a 3D framework in which Ln(III) polyhedra are interconnected by bridging {CPO(3)} tetrahedra into 2D inorganic layers parallel to the ab plane. The organic groups of H(2)L(-) are grafted on the two sides of the layer. These layers are further cross-linked by the bdc(2-) ligands from one layer to the Ln atoms from the other into a pillared-layered architecture with one-dimensional channel system along the a axis. The thermal stability of compounds has been investigated. Luminescent properties of compounds , and the magnetic properties of compound have also been studied.

  6. Bioactivity and phytochemical constituents of marine red seaweeds (Jania rubens, Corallina mediterranea and Pterocladia capillacea

    Directory of Open Access Journals (Sweden)

    Soad M. Mohy El-Din

    2016-07-01

    Full Text Available Seaweeds are potential renewable resources in the marine environment. The antibacterial activity of Jania rubens, Corallina mediterranea and Pterocladia capillacea were analyzed against human pathogenic bacteria. The present study was performed to investigate the phytochemical constituents of seaweeds, such as alkaloids, flavonoids, steroids, terpenoids and phlobatannins. In this study, we estimated phenols, flavonoids, tannins, pigments and mineral contents and determined the hydrogen peroxide scavenging activity, reducing power and total antioxidant activity of various extracts of selected seaweeds. Phytochemicals were extracted from the three seaweeds using various solvents, such as methanol, ethanol, acetone and chloroform. Among the various extracts, the methanolic extract was found to have the highest reducing power and total antioxidant capacity. We evaluated the seaweeds against Vibrio fluvialis, and Pterocladia capillacea was the most effective at controlling its growth. The highest zone of inhibition was recorded in the methanol extract. The chemical constituents of the seaweeds were characterized by GC–MS, which showed that they contain organic compounds, such as 1,2-benzenedicarboxylic acid.

  7. Two novel thorium organic frameworks constructed by bi- and tritopic ligands

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Fei [National Institute for Radiological Protection, Beijing (China). China CDC Key Lab. of Radiological Pretection and Nuclear Emergency; Chinese Academy of Sciences, Beijing (China). Inst. of High Energy Physics; Wang, Congzhi; Lan, Jianhui; Chai, Zhifang [Chinese Academy of Sciences, Beijing (China). Inst. of High Energy Physics; Ji, Yanqin [National Institute for Radiological Protection, Beijing (China). China CDC Key Lab. of Radiological Pretection and Nuclear Emergency

    2017-09-01

    Two thorium organic frameworks, Th(BDC){sub 2} and Th(OH)(BCPBA) have been hydrothermally synthesized using 1,4-benzenedicarboxylic acid (H{sub 2}BDC) and 3,5-bi(4-carboxyphenoxy)benzoic acid (H{sub 3}BCPBA), respectively. The obtained two compounds were determined by single-crystal XRD, and they exhibited two new topologies. Th(BDC){sub 2} shows a 3-dimensional (4,4,8)-connected framework with the Schlaefli symbol of (4{sup 14}.6{sup 12}.8{sup 2})(4{sup 2}.6{sup 3}.8)(4{sup 4}.6{sup 2}), and it is a mononuclear thorium(IV) complex. Th(OH)(BCPBA) possesses a (4,6)-connected topology with the Schlaefli symbol of (4{sup 15}){sup 2}(4{sup 6}){sup 3}, and it has a dinuclear thorium(IV) asymmetric unit with the shortest Th-Th distances. Viewing along suitable directions, channels with different shapes can be found in the obtained two frameworks. Based on calculation with PLATON, the amount of void space is 21.9% and 13.5% in Th(BDC){sub 2} and Th(OH)(BCPBA), respectively. Density functional theory (DFT) studies revealed that the metal-ligand interactions were mainly of ionic character in both compounds and the hydroxyl ions might play an important role in the stability of dinuclear thorium(IV) of Th(OH)(BCPBA).

  8. Hydrogen Storage Properties of Metal Nitroprussides M[Fe(CN)5NO], (M = Co, Ni)

    Energy Technology Data Exchange (ETDEWEB)

    Culp, J T; Matranga, C S; Smith, M; Bittner, E W; Bockrath, B C

    2006-04-27

    The volumetric hydrogen adsorption isotherms of two isostructural dehydrated cubic metal nitroprussides M[Fe(CN)5NO] (M = Co2+, Ni2+) have been measured up to a pressure of 760 Torr at 77 and 87 K. These materials are among the most efficient H2 sorbents based on porous coordination polymers reported to date. The H2 uptake in both materials is ~1.6 wt % at 77 K and 760 torr. These H2 capacities match those reported recently in the structurally related M3[Co(CN)6]2 compounds and are approximately 25% higher than those reported for Zn4O(1,4-benzenedicarboxylate)3 under the same conditions of temperature and pressure. The isosteric heats of H2 adsorption calculated from the 77 and 87 K isotherms for both materials were found to vary from ~7.5 kJ/mol at 0.40 wt % coverage to ~5.5 kJ/mol at 1.2 wt % coverage. The N2 BET surface areas were determined to be 634 m2/g and 523 m2/g for M = Ni and M = Co, respectively.

  9. Phytochemical Profile of Erythrina variegata by Using High-Performance Liquid Chromatography and Gas Chromatography-Mass Spectroscopy Analyses

    Directory of Open Access Journals (Sweden)

    Suriyavathana Muthukrishnan

    2016-08-01

    Full Text Available Natural products derived from plant sources have been utilized to treat patients with numerous diseases. The phytochemical constituents present in ethanolic leaf extract of Erythrina variegata (ELEV were identified by using high-performance liquid chromatography (HPLC and gas chromatography-mass spectroscopy (GC-MS analyses. Shade dried leaves were powdered and extracted with ethanol for analyses through HPLC to identify selected flavonoids and through GC-MS to identify other molecules. The HPLC analysis of ELEV showed the presence of gallic and caffeic acids as the major components at concentrations of 2.0 ppm and 0.1 ppm, respectively, as well as other components. GC-MS analysis revealed the presence of 3-eicosyne; 3,7,11,15-tetramethyl-2-hexadecen-1-ol; butanoic acid, 3-methyl-3,7-dimethyl-6-octenyl ester; phytol; 1,2-benzenedicarboxylic acid, diundecyl ester; 1-octanol, 2-butyl-; squalene; and 2H-pyran, 2-(7-heptadecynyloxy tetrahydro-derivative. Because pharmacopuncture is a new evolving natural mode that uses herbal extracts for treating patients with various ailments with minimum pain and maximum effect, the results of this study are particularly important and show that ELEV possesses a wide range of phytochemical constituents, as indicated above, as effective active principle molecules that can be used individually or in combination to treat patients with various diseases.

  10. 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.

  11. Destabilization in the isomeric nitrobenzonitriles: an experimental thermochemical study

    International Nuclear Information System (INIS)

    Roux, Maria Victoria; Jimenez, Pilar; Davalos, Juan Z.; Temprado, Manuel; Liebman, Joel F.

    2003-01-01

    The enthalpies of combustion and of sublimation, respectively, of the three isomeric nitrobenzonitriles have been measured: o-, {(-3456.3±2.9), (88.1±1.4)} kJ·mol -1 ; m-, {(-3442.8±3.3), (92.8±0.3)} kJ·mol -1 ; p-, {(-3448.2±3.6), (91.1±1.3)} kJ·mol -1 . In turn, from these values, the standard molar enthalpies of formation for the condensed and gaseous state, respectively, have been derived: o-, {(130.1±3.1), (218.2±3.4)} kJ·mol -1 ; m-, {(116.5±3.5), (209.3±3.5)} kJ·mol -1 ; p-, {(122.0±3.8), (213.1±4.0)} kJ·mol -1 . Destabilization energies associated with the presence of the two electron-withdrawing groups have been determined, for o-, m-, and p-nitrobenzonitrile, {(17.6±4.1), (8.7±4.2), and (12.5±4.6)} kJ·mol -1 , respectively, and are consistent with those obtained for the corresponding sets of isomeric methyl benzenedicarboxylates, dicyanobenzenes, dinitrobenzenes, and (neutral and ionized) nitrobenzoic acids

  12. On the direct synthesis of Cu(BDC) MOF nanosheets and their performance in mixed matrix membranes

    Energy Technology Data Exchange (ETDEWEB)

    Shete, Meera; Kumar, Prashant; Bachman, Jonathan E.; Ma, Xiaoli; Smith, Zachary P.; Xu, Wenqian; Mkhoyan, K. Andre; Long, Jeffrey R.; Tsapatsis, Michael

    2018-03-01

    High aspect-ratio nanosheets of metal-organic frameworks (MOFs) hold promise for use as selective flakes in gas separation membranes. However, simple and scalable methods for the synthesis of MOF nanosheets have thus far remained elusive. Here, we describe the direct synthesis of Cu(BDC) (BDC2-= 1,4-benzenedicarboxylate) nanosheets with an average lateral size of 2.5 mu m and a thickness of 25 nm from a well-mixed solution. Characterization of the nanosheets by powder and thin film X-ray diffraction, electron microscopy, and electron diffraction reveals pronounced structural disorder that may affect their pore structure. Incorporation of the Cu (BDC) nanosheets into a Matrimid polymer matrix results in mixed matrix membranes (MMMs) that exhibit a 70% increase in the CO2/CH4 selectivity compared with that of Matrimid. Analysis of new and previously reported permeation data for Cu(BDC) MMMs using a mathematical model for selective flake composites indicates that further performance improvements could be achieved with the selection of different polymers for use in the continuous phase.

  13. Identification of new phytoconstituents and antimicrobial activity in stem bark of Mangifera indica (L.).

    Science.gov (United States)

    Singh, Ruchi; Singh, S K; Maharia, R S; Garg, A N

    2015-02-01

    Mangifera indica, commonly called mango or amra belonging to a family of Anacardiaceae, is an important medicinal plant widely used in a variety of Ayurvedic preparations. Extract of its bark, leaves, flowers and kernels are being extensively used for curing various chronic diseases. Mango wood is used in yagya as base fire through which medicated smoke is generated. Three new compounds have been isolated from methanolic and hexane extracts of stem bark: 1,2-benzenedicarboxylic acid, mono(2-ethylhexyl)ester and 9,12-tetradecadiene-1-ol-acetate from the hexane extract and 3-chloro-N-(2-phenylethyl) propanamide from the methanolic extract. These were first separated by thin layer chromatography and later in a silica gel column and identified by characteristic infrared bands corresponding to respective functional groups. The compounds were further confirmed on the basis of GC-MS fragmentation pattern after comparing the data with NIST mass spectral database. All three compounds exhibited antimicrobial activity due to triterpenoids and flavonoids. Elemental analyses by INAA show it to be enriched in essential nutrient elements such as Ca, Fe, K, Mn and Zn which all play an important role in enzymatic processes. Copyright © 2014 Elsevier B.V. All rights reserved.

  14. Metal-organic frameworks as adsorbents for hydrogen purification and precombustion carbon dioxide capture.

    Science.gov (United States)

    Herm, Zoey R; Swisher, Joseph A; Smit, Berend; Krishna, Rajamani; Long, Jeffrey R

    2011-04-20

    Selected metal-organic frameworks exhibiting representative properties--high surface area, structural flexibility, or the presence of open metal cation sites--were tested for utility in the separation of CO(2) from H(2) via pressure swing adsorption. Single-component CO(2) and H(2) adsorption isotherms were measured at 313 K and pressures up to 40 bar for Zn(4)O(BTB)(2) (MOF-177, BTB(3-) = 1,3,5-benzenetribenzoate), Be(12)(OH)(12)(BTB)(4) (Be-BTB), Co(BDP) (BDP(2-) = 1,4-benzenedipyrazolate), H(3)[(Cu(4)Cl)(3)(BTTri)(8)] (Cu-BTTri, BTTri(3-) = 1,3,5-benzenetristriazolate), and Mg(2)(dobdc) (dobdc(4-) = 1,4-dioxido-2,5-benzenedicarboxylate). Ideal adsorbed solution theory was used to estimate realistic isotherms for the 80:20 and 60:40 H(2)/CO(2) gas mixtures relevant to H(2) purification and precombustion CO(2) capture, respectively. In the former case, the results afford CO(2)/H(2) selectivities between 2 and 860 and mixed-gas working capacities, assuming a 1 bar purge pressure, as high as 8.6 mol/kg and 7.4 mol/L. In particular, metal-organic frameworks with a high concentration of exposed metal cation sites, Mg(2)(dobdc) and Cu-BTTri, offer significant improvements over commonly used adsorbents, indicating the promise of such materials for applications in CO(2)/H(2) separations.

  15. Reversible Redox Activity in Multicomponent Metal-Organic Frameworks Constructed from Trinuclear Copper Pyrazolate Building Blocks.

    Science.gov (United States)

    Tu, Binbin; Pang, Qingqing; Xu, Huoshu; Li, Xiaomin; Wang, Yulin; Ma, Zhen; Weng, Linhong; Li, Qiaowei

    2017-06-14

    Inorganic functionalization of metal-organic frameworks (MOFs), such as incorporation of multiple inorganic building blocks with distinct metals into one structure and further modulation of the metal charges, endows the porous materials with significant properties toward their applications in catalysis. In this work, by an exploration of the role of 4-pyrazolecarboxylic acid (H 2 PyC) in the formation of trinuclear copper pyrazolate as a metalloligand in situ, four new MOFs with multiple components in order were constructed through one-pot synthesis. This metalloligand strategy provides multicomponent MOFs with new topologies (tub for FDM-4 and tap for FDM-5) and is also compatible with a second organic linker for cooperative construction of complex MOFs (1,4-benzenedicarboxylic acid for FDM-6 and 2,6-naphthalenedicarboxylic acid for FDM-7). The component multiplicity of these MOFs originates from PyC's ability to separate Cu and Zn on the basis of their differentiated binding affinities toward pyrazolate and carboxylate. These MOFs feature reversible and facile redox transformations between Cu I 3 (PyC) 3 and Cu II 3 (μ-OH)(PyC) 3 (OH) 3 without altering the connecting geometries of the units, thus further contributing to the significant catalytic activities in the oxidation of CO and aromatic alcohols and the decomposition of H 2 O 2 . This study on programming multiple inorganic components into one framework and modulating their electronic structures is an example of functionalizing the inorganic units of MOFs with a high degree of control.

  16. Mesoscopic superstructures of flexible porous coordination polymers synthesizedviacoordination replication.

    Science.gov (United States)

    Sumida, Kenji; Moitra, Nirmalya; Reboul, Julien; Fukumoto, Shotaro; Nakanishi, Kazuki; Kanamori, Kazuyoshi; Furukawa, Shuhei; Kitagawa, Susumu

    2015-10-01

    The coordination replication technique is employed for the direct conversion of a macro- and mesoporous Cu(OH) 2 -polyacrylamide composite to three-dimensional superstructures consisting of the flexible porous coordination polymers, Cu 2 (bdc) 2 (MeOH) 2 and Cu 2 (bdc) 2 (bpy) (bdc 2- = 1,4-benzenedicarboxylate, bpy = 4,4'-bipyridine). Detailed characterization of the replicated systems reveals that the structuralization plays an important role in determining the adsorptive properties of the replicated systems, and that the immobilization of the crystals within a higher-order architecture also affects its structural and dynamic properties. The polyacrylamide polymer is also found to be crucial for maintaining the structuralization of the monolithic systems, and in providing the mechanical robustness required for manual handling. In all, the results discussed here demonstrate a significant expansion in the scope of the coordination replication strategy, and further confirms its utility as a highly versatile platform for the preparation of functional three-dimensional superstructures of porous coordination polymers.

  17. A new cadmium(II coordination polymer constructed by 2-(2-chloro-6-fluorophenyl-1H-imidazo[4,5-f][1,10]-phenanthroline and 1,3-benzenecarboxylate: Synthesis, crystal structure, thermal behavior and luminescent property

    Directory of Open Access Journals (Sweden)

    Kong Zhi-Guo

    2014-01-01

    Full Text Available A new Cd(II coordination polymer, namely, [Cd2(Cl(1,3-BDC1.5(L2]•1.25H2O (1 (L = 2-(2-chloro-6-fluorophenyl-1H-imidazo[4,5-f][1,10]phenanthroline and 1,3-BDC = 1,3-benzenedicarboxylate, has been synthesized under hydrothermal condition. The crystal of 1 belongs to orthorhombic, space group P bcn with a = 31.3116(19 Å, b = 13.5485(8 Å, c = 22.9850(15 Å, α = 90º, β = 90º, γ = 90°, C50H28.5Cd2Cl3F2N8O7.25, Mr = 1226.46, V = 9750.8(10 Å3, Z = 8, Dc = 1.671 g/cm3, S = 1.038, μ(MoKα = 1.106 mm-1, F(000 = 4860, R = 0.0585 and wR = 0.1485. Compound 1 shows a 1D ladder structure. Further, neighboring 1D ladders are joined together by π•••π interactions to result in a 2D supramolecular layer. The thermal behavior of 1 has been characterized. In addition, its luminescent property has been studied in solid state at room temperature.

  18. 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.

  19. Effects of ligand functionalization on the photocatalytic properties of titanium-based MOF: A density functional theory study

    Directory of Open Access Journals (Sweden)

    Yi Li

    2018-03-01

    Full Text Available The first principle calculations have been performed to investigate the geometries, band structures and optical absorptions of a series of MIL-125 MOFs, in which the 1,4-benzenedicarboxylate (BDC linkers are modified by different types and amounts of chemical groups, including NH2, OH, and NO2. Our results indicate that new energy bands will appear in the band gap of pristine MIL-125 after introducing new group into BDC linker, but the components of these band gap states and the valence band edge position are sensitive to the type of functional group as well as the corresponding amount. Especially, only the incorporation of amino group can obviously decrease the band gap of MIL-125, and the further reduction of the band gap can be observed if the amount of NH2 is increased. Although MIL-125 functionalized by NH2 group exhibits relatively weak or no activity for the photocatalytic O2 evolution by splitting water, such ligand modification can effectively improve the efficiency in H2 production because now the optical absorption in the visible light region is significantly enhanced. Furthermore, the adsorption of water molecule becomes more favorable after introducing of amino group, which is also beneficial for the water-splitting reaction. The present study can provide theoretical insights to design new photocatalysts based on MIL-125.

  20. Facile preparation of magnetic metal organic frameworks core–shell nanoparticles for stimuli-responsive drug carrier

    Science.gov (United States)

    Li, Sheng; Bi, Ke; Xiao, Ling; Shi, Xiaowen

    2017-12-01

    Facile synthesis of core–shell magnetic MOFs for drug delivery is of significance due to the advantages of high drug load and easy separation. In this work, magnetic metal organic frameworks (MOFs, Fe3O4-NH2@MIL101-NH2) core–shell nanoparticles were synthesized rapidly in water phase by microwave irradiation using Fe3+ and 2-amino-1,4-benzenedicarboxylate (BDC-NH2) as metal ions and ligands respectively. The resulting magnetic MOFs exhibit large surface areas (96.04 m2 g‑1), excellent magnetic response (20.47 emu g‑1) and large mesopore volume (22.07 cm3 g‑1) along with spherical morphologies with the diameters ranging from 140–330 nm. Using doxorubicin (DOX) as a model drug, the drug loading capacity of Fe3O4-NH2@MIL101-NH2 could reach 36.02%, substantially higher than pristine MIL101-NH2. Importantly, the release of DOX could be controlled by pH as well as the meso pore size of MOFs. The cytotoxicity assay showed that the magnetic MOFs have low cytotoxicity and good biocompatibility. The results suggest great potential of the magnetic MOFs core–shell nanoparticles fabricated in this study on controlled drug release of DOX.

  1. Review of Phthalates Exposure and Toxicity

    Directory of Open Access Journals (Sweden)

    Samaneh Taghilou

    2015-12-01

    Full Text Available The dialkyl- or alkyl/aryl esters of 1, 2-benzenedicarboxylic acid, which are known as Phthalates, are high-production volume synthetic chemicals and considered as environmental pollutants, due to high production and uses in community, plastics industry and common consuming products. Di-(2-ethylhexyl phthalate (DEHP is the most abundant phthalate in the environment. Human exposure with DEHP could be done via different chemical compounds including food packaging, household furnishings, nutritional supplements, cleaning materials and insecticides. Besides, exposure of human with phthalates occurs through different pathways such as direct contact and using Phthalate-containing products, and indirectly through leaching into other products, or general environmental contaminations. Historically, the diet has been considered the major source of phthalate exposure in the general population, but in all sources, pathways, and their relative contributions to human exposures are not well understood. Medical devices are other source of significant exposure in human. Furthermore, cosmetics, personal care products, pharmaceuticals, nutritional supplements, herbal remedies and insecticides, may result in significant but poorly quantified human exposure with this compounds. In the present review article, we tried to discuss about metabolism of phthalates in human, toxicity, monitoring of phthalates in foods, environment, and cosmetic products and then metabolites of phthalates. Finally, evaluation of human exposure through biological control is discussed.

  2. Effects of ligand functionalization on the photocatalytic properties of titanium-based MOF: A density functional theory study

    Science.gov (United States)

    Li, Yi; Fu, Yuqing; Ni, Bilian; Ding, Kaining; Chen, Wenkai; Wu, Kechen; Huang, Xin; Zhang, Yongfan

    2018-03-01

    The first principle calculations have been performed to investigate the geometries, band structures and optical absorptions of a series of MIL-125 MOFs, in which the 1,4-benzenedicarboxylate (BDC) linkers are modified by different types and amounts of chemical groups, including NH2, OH, and NO2. Our results indicate that new energy bands will appear in the band gap of pristine MIL-125 after introducing new group into BDC linker, but the components of these band gap states and the valence band edge position are sensitive to the type of functional group as well as the corresponding amount. Especially, only the incorporation of amino group can obviously decrease the band gap of MIL-125, and the further reduction of the band gap can be observed if the amount of NH2 is increased. Although MIL-125 functionalized by NH2 group exhibits relatively weak or no activity for the photocatalytic O2 evolution by splitting water, such ligand modification can effectively improve the efficiency in H2 production because now the optical absorption in the visible light region is significantly enhanced. Furthermore, the adsorption of water molecule becomes more favorable after introducing of amino group, which is also beneficial for the water-splitting reaction. The present study can provide theoretical insights to design new photocatalysts based on MIL-125.

  3. 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.

  4. An Insecticidal Compound Produced by an Insect-Pathogenic Bacterium Suppresses Host Defenses through Phenoloxidase Inhibition

    Directory of Open Access Journals (Sweden)

    Ihsan Ullah

    2014-12-01

    Full Text Available A bioassay-guided column chromatographic strategy was adopted in the present study to fractionate the culture extract of Photorhabdus temperata M1021 to identify potential insecticidal and antimicrobial compounds. An ethyl acetate (EtOAc culture extract of P. temperata was assayed against Galleria mellonella larvae through intra-hemocoel injection and exhibited 100% insect mortality within 60 h. The EtOAc fraction and an isolated compound exhibited phenoloxidase (PO inhibition of up to 60% and 63%, respectively. The compound was identified as 1,2-benzenedicarboxylic acid (phthalic acid, PA by gas chromatography-mass spectrometry and nuclear magnetic resonance. PA exhibited insecticidal activity against G. mellonella in a dose-dependent manner, and 100% insect mortality was observed at 108 h after injection of 1 M PA. In a PO inhibition assay, 0.5 and 1 M concentrations of PA were found to inhibit PO activity by 74% and 82%, respectively; and in a melanotic nodule formation assay, nodule formation was significantly inhibited (27 and 10 nodules by PA (0.5 and 1 M, respectively. PA was furthermore found to have substantial antioxidant activity and maximum antioxidant activity was 64.7% for 0.5 M PA as compare to control. Antibacterial activity was assessed by The MIC values ranged from 0.1 M to 0.5 M of PA. This study reports a multifunctional PA, a potential insecticidal agent, could a factor of insect mortality along with other toxins produced by P. temperata M1021.

  5. Fabrication of a polymeric composite incorporating metal-organic framework nanosheets for solid-phase microextraction of polycyclic aromatic hydrocarbons from water samples

    Energy Technology Data Exchange (ETDEWEB)

    Wei, Songbo; Lin, Wei; Xu, Jianqiao [MOE Key Laboratory of Aquatic Product of Safety/KLGHEI of Environment and Energy Chemistry, School of Chemistry, Sun Yat-sen University, Guangzhou 510275 (China); Wang, Ying [School of Pharmacy, Guiyang Medical University, Guiyang 550004 (China); Liu, Shuqin; Zhu, Fang [MOE Key Laboratory of Aquatic Product of Safety/KLGHEI of Environment and Energy Chemistry, School of Chemistry, Sun Yat-sen University, Guangzhou 510275 (China); Liu, Yuan, E-mail: yliu@shou.edu.cn [College of Food Science & Technology, Shanghai Ocean University, Shanghai 201306 (China); Ouyang, Gangfeng, E-mail: cesoygf@mail.sysu.edu.cn [MOE Key Laboratory of Aquatic Product of Safety/KLGHEI of Environment and Energy Chemistry, School of Chemistry, Sun Yat-sen University, Guangzhou 510275 (China)

    2017-06-08

    In this contribution, it was discovered that even distribution of a metal-organic framework (MOF) [e.g. copper 1,4-benzenedicarboxylate (CBDC)] within polymeric matrixes (e.g. polyimide) resulted in a high-efficient coating material on the surface of a stainless steel wire (SSW). Consequently, a home-made solid phase microextraction (SPME) fiber was fabricated for fast determination of target analytes in real water samples. Scanning electron microscope images indicated that the coating possessed homogenously porous surface. Coupled with gas chromatography-mass spectrometry (GC-MS) and direct immersion SPME (DI-SPME) technique, the fiber was evaluated through the analysis of five polycyclic aromatic hydrocarbons (PAHs) in aqueous samples. Under optimized extraction and desorption conditions, the established method based on the home-made fiber exhibited good repeatability (4.2–12.7%, n = 6) and reproducibility (0.9–11.7%, n = 3), low limits of detection (LODs, 0.11–2.10 ng L{sup −1}), low limits of quantification (LOQs, 0.36–6.99 ng L{sup −1}) and wide linear ranges (20–5000 ng L{sup −1}). Eventually, the method was proven applicable in the determination of PAHs in real samples, as the recoveries were in a satisfactory range (81.7–116%). - Highlights: • A homogenously porous CBDC@polyimide-coated fiber was fabricated and characterized. • The fiber exhibited highly desired extraction performance towards PAHs. • The fiber was employed for the determination of PAHs in real aqueous samples.

  6. Design of Pore Size and Functionality in Pillar-Layered Zn-Triazolate-Dicarboxylate Frameworks and Their High CO2/CH4 and C2 Hydrocarbons/CH4 Selectivity.

    Science.gov (United States)

    Zhai, Quan-Guo; Bai, Ni; Li, Shu'ni; Bu, Xianhui; Feng, Pingyun

    2015-10-19

    In the design of new materials, those with rare and exceptional compositional and structural features are often highly valued and sought after. On the other hand, materials with common and more accessible modes can often provide richer and unsurpassed compositional and structural variety that makes them a more suitable platform for systematically probing the composition-structure-property correlation. We focus here on one such class of materials, pillar-layered metal-organic frameworks (MOFs), because different pore size and shape as well as functionality can be controlled and adjusted by using pillars with different geometrical and chemical features. Our approach takes advantage of the readily accessible layered Zn-1,2,4-triazolate motif and diverse dicarboxylate ligands with variable length and functional groups, to prepare seven Zn-triazolate-dicarboxylate pillar-layered MOFs. Six different gases (N2, H2, CO2, C2H2, C2H4, and CH4) were used to systematically examine the dependency of gas sorption properties on chemical and geometrical properties of those MOFs as well as their potential applications in gas storage and separation. All of these pillar-layered MOFs show not only remarkable CO2 uptake capacity, but also high CO2 over CH4 and C2 hydrocarbons over CH4 selectivity. An interesting observation is that the BDC ligand (BDC = benzenedicarboxylate) led to a material with the CO2 uptake outperforming all other metal-triazolate-dicarboxylate MOFs, even though most of them are decorated with amino groups, generally believed to be a key factor for high CO2 uptake. Overall, the data show that the exploration of the synergistic effect resulting from combined tuning of functional groups and pore size may be a promising strategy to develop materials with the optimum integration of geometrical and chemical factors for the highest possible gas adsorption capacity and separation performance.

  7. A novel photo-active Cd:1,4-benzene dicarboxylate metal organic framework templated using [Ru(ii)(2,2'-bipyridine)3]2+: synthesis and photophysics of RWLC-5.

    Science.gov (United States)

    Larsen, Randy W; Mayers, Jacob M; Wojtas, Lukasz

    2017-09-26

    The development of photoactive porous materials is of significant importance for applications ranging from sustainable energy to pharmaceutical development and catalysis. A particularly attractive class of photo-active materials is the metal-organic framework (MOF)-based platform in which the photo-active elements are components of the framework itself or photo-active guests encapsulated within the MOF cavities. It has now been demonstrated that the photo-active [Ru(2,2'-bipyridine) 3 ] 2+ (RuBpy) complex can template the formation of MOFs with varying three dimensional structures. Here we report the synthesis and structural and photo-physical characterization of a new RuBpy-templated MOF composed of Cd 2+ ions with 1,4-benzenedicarboxylate ligands (RWLC-5) that contains crystallographically resolved RuBpy complexes. The new material displays a biphasic emission decay (130 ns and 1180 ns, T = 20 °C) and a bathochromically shifted emission maximum, relative to RuBpy in solution (603 nm for RuBpy in ethanol vs. 630 nm for RWLC-5). The emission lifetimes also do not display temperature-dependent decays which are characteristic of RuBpy type complexes as well as other RuBpy templated MOFs. The lack of temperature dependence is consistent with the complete deactivation of the 3 LF state of the encapsulated RuBpy complex due to a constrained environment. The fast phase decay is attributed to a water molecule hydrogen bonded to a bipyridine ligand associated with ∼38% of the encapsulated RuBpy complexes resulting in the nonradiative deactivation of the 3 MLCT state.

  8. Hybrid materials based on novel 2D lanthanide coordination polymers covalently bonded to amine-modified SBA-15 and MCM-41: assembly, characterization, structural features, thermal and luminescence properties.

    Science.gov (United States)

    Wang, Jun; Dou, Wei; Kirillov, Alexander M; Liu, Weisheng; Xu, Cailing; Fang, Ran; Yang, Lizi

    2016-11-22

    Three novel 2D coordination polymers [Tb 2 (μ 4 -L) 2 (μ-HL)(μ-HCOO)(DEF)] n (Tb-L), [Eu(μ 4 -L)(L)(H 2 O) 2 ] n (Eu-L), and [Nd(μ 4 -L)(L)(H 2 O) 2 ] n (Nd-L) were assembled from the corresponding lanthanide(iii) nitrates and 5 methoxy-(4-benzaldehyde)-1,3-benzenedicarboxylic acid (H 2 L) as a main multifunctional building block bearing carboxylate and aldehyde functional groups, using H 2 O/DEF {DEF = N,N-diethylformamide} as a reaction medium. The obtained coordination polymers were isolated as stable microcrystalline solids and fully characterized by elemental analysis, FT-IR spectroscopy, TGA, BET, PXRD, and single-crystal X-ray diffraction methods. Their structures feature intricate 2D metal-organic networks, which were topologically classified as underlying layers with the 4,6L26 (for Tb-L) or sql (for Eu-L and Nd-L) topologies. Besides, a novel series of mesoporous hybrid materials wherein the Tb-L, Eu-L, or Nd-L coordination polymers are covalently grafted into the amine-functionalized SBA-15-NH 2 or MCM-41-NH 2 matrices (via the formation of Schiff-base groups) was also synthesized and fully characterized. These hybrid materials show high thermal and photoluminescence stability, as well as remarkable chemical resistance to boiling water, and acidic or alkaline medium. Luminescent properties of the parent coordination polymers and derived hybrid materials are investigated in detail, showing that the latter combine the luminescent characteristics (intense green or red emissions and excellent stability) of lanthanide coordination polymers and structural features of ordered mesoporous silica molecular sieves. Moreover, light emitting devices were assembled, by coating the hybrid materials onto the surface of UV-LED bulbs, and showed excellent light emitting properties.

  9. Fabrication of a polymeric composite incorporating metal-organic framework nanosheets for solid-phase microextraction of polycyclic aromatic hydrocarbons from water samples

    International Nuclear Information System (INIS)

    Wei, Songbo; Lin, Wei; Xu, Jianqiao; Wang, Ying; Liu, Shuqin; Zhu, Fang; Liu, Yuan; Ouyang, Gangfeng

    2017-01-01

    In this contribution, it was discovered that even distribution of a metal-organic framework (MOF) [e.g. copper 1,4-benzenedicarboxylate (CBDC)] within polymeric matrixes (e.g. polyimide) resulted in a high-efficient coating material on the surface of a stainless steel wire (SSW). Consequently, a home-made solid phase microextraction (SPME) fiber was fabricated for fast determination of target analytes in real water samples. Scanning electron microscope images indicated that the coating possessed homogenously porous surface. Coupled with gas chromatography-mass spectrometry (GC-MS) and direct immersion SPME (DI-SPME) technique, the fiber was evaluated through the analysis of five polycyclic aromatic hydrocarbons (PAHs) in aqueous samples. Under optimized extraction and desorption conditions, the established method based on the home-made fiber exhibited good repeatability (4.2–12.7%, n = 6) and reproducibility (0.9–11.7%, n = 3), low limits of detection (LODs, 0.11–2.10 ng L −1 ), low limits of quantification (LOQs, 0.36–6.99 ng L −1 ) and wide linear ranges (20–5000 ng L −1 ). Eventually, the method was proven applicable in the determination of PAHs in real samples, as the recoveries were in a satisfactory range (81.7–116%). - Highlights: • A homogenously porous CBDC@polyimide-coated fiber was fabricated and characterized. • The fiber exhibited highly desired extraction performance towards PAHs. • The fiber was employed for the determination of PAHs in real aqueous samples.

  10. Comprehensive study of carbon dioxide adsorption in the metal–organic frameworks M₂(dobdc) (M = Mg, Mn, Fe, Co, Ni, Cu, Zn)

    Energy Technology Data Exchange (ETDEWEB)

    Queen, Wendy L. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Hudson, Matthew R. [National Institute of Standards and Technology, Gaithersburg, MD (United States); Bloch, Eric D. [Univ. of California, Berkeley, CA (United States); Mason, Jarad A. [Univ. of California, Berkeley, CA (United States); Gonzalez, Miguel I. [Univ. of California, Berkeley, CA (United States); Lee, Jason S. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Univ. of California, Berkeley, CA (United States); Gygi, David [Univ. of California, Berkeley, CA (United States); Howe, Joshua D. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Univ. of California, Berkeley, CA (United States); Lee, Kyuho [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Univ. of California, Berkeley, CA (United States); Darwish, Tamim A. [Australian Nuclear Science and Technology Organisation, Lucas Heights (Australia); James, Michael [Australian Nuclear Science and Technology Organisation, Lucas Heights (Australia); Australian Synchrotron, Clayton (Australia); Peterson, Vanessa K. [Australian Nuclear Science and Technology Organisation, Lucas Heights (Australia); Teat, Simon J. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Smit, Berend [Univ. of California, Berkeley, CA (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Ecole Polytechnique Federale de Lausanne (EPFL), Lausanne (Switzerland); Neaton, Jeffrey B. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Univ. of California, Berkeley, CA (United States); Long, Jeffrey R. [Univ. of California, Berkeley, CA (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Brown, Craig M. [National Institute of Standards and Technology, Gaithersburg, MD (United States); Univ. of Delaware, Newark, DE (United States)

    2014-01-01

    Analysis of the CO₂ adsorption properties of a well-known series of metal–organic frameworks M₂(dobdc) (dobdc⁴⁻ = 2,5-dioxido-1,4-benzenedicarboxylate; M = Mg, Mn, Fe, Co, Ni, Cu, and Zn) is carried out in tandem with in situ structural studies to identify the host–guest interactions that lead to significant differences in isosteric heats of CO₂ adsorption. Neutron and X-ray powder diffraction and single crystal X-ray diffraction experiments are used to unveil the site-specific binding properties of CO₂ within many of these materials while systematically varying both the amount of CO₂ and the temperature. Unlike previous studies, we show that CO₂ adsorbed at the metal cations exhibits intramolecular angles with minimal deviations from 180°, a finding that indicates a strongly electrostatic and physisorptive interaction with the framework surface and sheds more light on the ongoing discussion regarding whether CO₂ adsorbs in a linear or nonlinear geometry. This has important implications for proposals that have been made to utilize these materials for the activation and chemical conversion of CO₂. For the weaker CO₂ adsorbents, significant elongation of the metal–O(CO₂) distances are observed and diffraction experiments additionally reveal that secondary CO₂ adsorption sites, while likely stabilized by the population of the primary adsorption sites, significantly contribute to adsorption behavior at ambient temperature. Density functional theory calculations including van der Waals dispersion quantitatively corroborate and rationalize observations regarding intramolecular CO₂ angles and trends in relative geometric properties and heats of adsorption in the M₂(dobdc)–CO₂ adducts.

  11. Interdiffusion Reaction-Assisted Hybridization of Two-Dimensional Metal-Organic Frameworks and Ti3C2Tx Nanosheets for Electrocatalytic Oxygen Evolution.

    Science.gov (United States)

    Zhao, Li; Dong, Biliang; Li, Shaozhou; Zhou, Lijun; Lai, Linfei; Wang, Zhiwei; Zhao, Shulin; Han, Min; Gao, Kai; Lu, Min; Xie, Xiaoji; Chen, Bo; Liu, Zhengdong; Wang, Xiangjing; Zhang, Hao; Li, Hai; Liu, Juqing; Zhang, Hua; Huang, Xiao; Huang, Wei

    2017-06-27

    Two-dimensional (2D) metal-organic framework (MOF) nanosheets have been recently regarded as the model electrocatalysts due to their porous structure, fast mass and ion transfer through the thickness, and large portion of exposed active metal centers. Combining them with electrically conductive 2D nanosheets is anticipated to achieve further improved performance in electrocatalysis. In this work, we in situ hybridized 2D cobalt 1,4-benzenedicarboxylate (CoBDC) with Ti 3 C 2 T x (the MXene phase) nanosheets via an interdiffusion reaction-assisted process. The resulting hybrid material was applied in the oxygen evolution reaction and achieved a current density of 10 mA cm -2 at a potential of 1.64 V vs reversible hydrogen electrode and a Tafel slope of 48.2 mV dec -1 in 0.1 M KOH. These results outperform those obtained by the standard IrO 2 -based catalyst and are comparable with or even better than those achieved by the previously reported state-of-the-art transition-metal-based catalysts. While the CoBDC layer provided the highly porous structure and large active surface area, the electrically conductive and hydrophilic Ti 3 C 2 T x nanosheets enabled the rapid charge and ion transfer across the well-defined Ti 3 C 2 T x -CoBDC interface and facilitated the access of aqueous electrolyte to the catalytically active CoBDC surfaces. The hybrid nanosheets were further fabricated into an air cathode for a rechargeable zinc-air battery, which was successfully used to power a light-emitting diode. We believe that the in situ hybridization of MXenes and 2D MOFs with interface control will provide more opportunities for their use in energy-based applications.

  12. Selective binding of O2 over N2 in a redox-active metal-organic framework with open iron(II) coordination sites.

    Science.gov (United States)

    Bloch, Eric D; Murray, Leslie J; Queen, Wendy L; Chavan, Sachin; Maximoff, Sergey N; Bigi, Julian P; Krishna, Rajamani; Peterson, Vanessa K; Grandjean, Fernande; Long, Gary J; Smit, Berend; Bordiga, Silvia; Brown, Craig M; Long, Jeffrey R

    2011-09-21

    The air-free reaction between FeCl(2) and H(4)dobdc (dobdc(4-) = 2,5-dioxido-1,4-benzenedicarboxylate) in a mixture of N,N-dimethylformamide (DMF) and methanol affords Fe(2)(dobdc)·4DMF, a metal-organic framework adopting the MOF-74 (or CPO-27) structure type. The desolvated form of this material displays a Brunauer-Emmett-Teller (BET) surface area of 1360 m(2)/g and features a hexagonal array of one-dimensional channels lined with coordinatively unsaturated Fe(II) centers. Gas adsorption isotherms at 298 K indicate that Fe(2)(dobdc) binds O(2) preferentially over N(2), with an irreversible capacity of 9.3 wt %, corresponding to the adsorption of one O(2) molecule per two iron centers. Remarkably, at 211 K, O(2) uptake is fully reversible and the capacity increases to 18.2 wt %, corresponding to the adsorption of one O(2) molecule per iron center. Mössbauer and infrared spectra are consistent with partial charge transfer from iron(II) to O(2) at low temperature and complete charge transfer to form iron(III) and O(2)(2-) at room temperature. The results of Rietveld analyses of powder neutron diffraction data (4 K) confirm this interpretation, revealing O(2) bound to iron in a symmetric side-on mode with d(O-O) = 1.25(1) Å at low temperature and in a slipped side-on mode with d(O-O) = 1.6(1) Å when oxidized at room temperature. Application of ideal adsorbed solution theory in simulating breakthrough curves shows Fe(2)(dobdc) to be a promising material for the separation of O(2) from air at temperatures well above those currently employed in industrial settings.

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

    KAUST Repository

    Luo, Feng

    2016-04-26

    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 wellestablished 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 Zn2+ 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 cm3/cm3) to Zn-MOF-74. Interestingly, the accessible Zn2+ 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 cm3/cm3) than Zn-MOF-74 (146 cm3/cm3) 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. © 2016 American Chemical Society.

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

    Science.gov (United States)

    Scott, Andrea Michalkova; Petrova, Tetyana; Odbadrakh, Khorgolkhuu; Nicholson, Donald M; Fuentes-Cabrera, Miguel; Lewis, James P; Hill, Frances C; Leszczynski, Jerzy

    2012-07-01

    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.

  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. Isolation and characterization of an n-hexadecane degrading Acinetobacter baumannii KSS1060 from a petrochemical wastewater treatment plant

    International Nuclear Information System (INIS)

    Shiri, Z.; Kermanshahi, R. K.; Soudi, M. R.; Farajzadeh, D.

    2015-01-01

    Hydrocarbons are widespread in the environment, but because of the massive utilization of petroleum products, they are nowadays strongly involved in environmental pollution. Bioremediation is the obliging technology for the treatment of hydrocarbon-contaminated sites. Therefore, to investigate the potential of petrochemical hydrocarbon (HC)-degrading indigenous microorganisms in wastewater samples collected from Fajr petrochemical wastewater treatment plants, a strain of Acinetobacter baumannii was isolated from this hydrocarbon-contaminated wastewater and examined for its ability to utilize hexadecane. This strain was capable to grow on n-hexadecane as the sole source of carbon and energy. The ability of the isolate to degrade n-hexadecane was assessed by growth assays and gas chromatography/mass spectrometry analysis. Using GC analysis, it was shown that the strain KSS1060 was able to degrade 62 % of n-hexadecane within 6 days, which mostly (51.6 %) occurred within the first 24 h. Identification of this hexadecane-degrader bacterium was carried out using 16S rDNA sequence analysis. Additionally, characterization of chemical composition of wastewater samples by the use of gas chromatography/mass spectrometry analysis indicated the presence of Hexanal, Benzene methanol, Indanol, 1,2-benzenedicarboxylic acid diethyl ester, diisobutyl phthalate, and Phenol,4,4′-(1-methylethylidene) in the major constituents of wastewater. In conclusion, this study can focus on more cost-efficient applications of native bacterial strains for the large-scale biodegradation of wastewater samples from petrochemical plant in industry, where it causes disturbing problems due to its harmful effects on different organisms and human beings.

  17. 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

    International Nuclear Information System (INIS)

    Ahmed, Imteaz; Jhung, Sung Hwa

    2016-01-01

    Highlights: • Metal-organic frameworks (MIL-101) were composed with graphene oxide (GnO). • GnO/MIL-101 showed the highest adsorption capacity for indole and quinoline. • Adsorption mechanism was clearly shown based on adsorption results and FTIR. • GnO/MIL-101 might be applied commercially considering capacity and reusability. - Abstract: 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.

  18. 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

    Energy Technology Data Exchange (ETDEWEB)

    Ahmed, Imteaz; Jhung, Sung Hwa, E-mail: sung@knu.ac.kr

    2016-08-15

    Highlights: • Metal-organic frameworks (MIL-101) were composed with graphene oxide (GnO). • GnO/MIL-101 showed the highest adsorption capacity for indole and quinoline. • Adsorption mechanism was clearly shown based on adsorption results and FTIR. • GnO/MIL-101 might be applied commercially considering capacity and reusability. - Abstract: 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.

  19. 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.

  20. Four Mixed-Ligand Zn(II Three-Dimensional Metal-Organic Frameworks: Synthesis, Structural Diversity, and Photoluminescent Property

    Directory of Open Access Journals (Sweden)

    Chih-Chieh Wang

    2017-11-01

    Full Text Available Assemblies of four three-dimensional (3D mixed-ligand coordination polymers (CPs having formulas, {[Zn2(bdc2(4-bpdh]·C2H5OH·2H2O}n (1, [Zn(bdc(4-bpdh]n (2, {[Zn2(bdc2(4-bpdh2]·(4-bpdh}n (3, and {[Zn(bdc(4-bpdh]·C2H5OH}n (4 (bdc2− = dianion of 1,4-benzenedicarboxylic acid, 4-bpdh = 2,5-bis(4-pyridyl-3,4-diaza-2,4-hexadiene have been synthesized and structurally characterized by single-crystal X-ray diffraction method. Structural determination reveals that the coordination numbers (geometry of Zn(II ions in 1, 2, 3, and 4 are five (distorted square-pyramidal (SP, six (distorted octahedral (Oh, five (trigonal-bipyramidal (TBP, and four (tetrahedral (Td, respectively, and are bridged by 4-bpdh with bis-monodentate coordination mode and bdc2− ligands with bis-bidentate in 1, chelating/bidentate in 2, bis-monodentate and bis-bidentate in 3, and bis-monodentate in 4, to generate two-fold interpenetrating 3D cube-like metal-organic framework (MOF with pcu topology, non-interpenetrating 3D MOF, two-fold interpenetrating 3D rectangular-box-like MOF with pcu topology and five-fold interpenetrating diamondoid-like MOF with dia topology, respectively. These different intriguing architectures indicate that the coordination numbers and geometries of Zn(II ions, coordination modes of bdc2− ligand, and guest molecules play important roles in the construction of MOFs and the formation of the structural topologies and interpenetrations. Thermal stabilities, and photoluminescence study of 1–4 were also studied in detail. The complexes exhibit ligands based photoluminescence properties at room temperature.

  1. 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.

  2. Syntheses, structures and photoelectric properties of a series of Cd(II)/Zn(II) coordination polymers and coordination supramolecules

    International Nuclear Information System (INIS)

    Jin Jing; Han Xiao; Meng Qin; Li Dan; Chi Yuxian; Niu Shuyun

    2013-01-01

    Five Cd(II)/Zn(II) complexes [Cd(1,2-bdc)(pz) 2 (H 2 O)] n (1), [Cd1Cd2(btec)(H 2 O) 6 ] n (2), [Cd(3,4-pdc) (H 2 O)] n (3), [Zn(2,5-pdc)(H 2 O) 4 ]·2H 2 O (4) and { [Zn(2,5-pdc)(H 2 O) 2 ]·H 2 O} n (5) (H 2 bdc=1,2-benzenedicarboxylic acid, pz=pyrazole, H 4 btec=1,2,4,5-benzenetetracarboxylic acid, H 2 pdc=pyridine-dicarboxylic acid) were hydrothermally synthesized and characterized by single-crystal X-ray diffraction, surface photovoltage spectroscopy, XRD, TG analysis, IR and UV–vis spectra and elemental analysis. Structural analyses show that complexes 1–3 are 1D, 2D and 3D Cd(II) coordination polymers, respectively. Complex 4 is a mononuclear Zn(II) complex. Complex 5 is a 3D Zn(II) coordination polymer. The surface photoelectric properties of complexes were investigated by SPS. The results indicate that all complexes exhibit photoelectric responses in the range of 300–600 nm, which reveals that they all possess certain photoelectric conversion properties. By the comparative analyses, it can be found that the species and coordination micro-environment of central metal ion, the species and property of ligands affect the intensity and scope of photoelectric response. - Graphical abstract: Five Cd(II)/Zn(II) complexes have been hydrothermally synthesized and characterized. The photoelectric properties were studied with SPS. The species and coordination micro-environment of central metal ion, the species and property of ligands all affect the photoelectric responses. Highlights: ► Five Cd/Zn complexes have been synthesized and characterized. ► The SPS results indicate they possess obvious photoelectric conversion property. ► The species and coordination environment of central metal ion affect SPS. ► The species and property of ligands affect SPS. ► By the energy-band theory and the crystal filed theory, the SPS are analyzed and assigned.

  3. Davisson-Germer Prize Talk: Hydrogen storage in nanoporous materials

    Science.gov (United States)

    Chabal, Yves

    2009-03-01

    To develop a hydrogen-based energy technology, several classes of materials are being considered to achieve the DOE targets for gravimetric and volumetric hydrogen densities for hydrogen storage, including liquids (e.g. ammonium borohydrides), clathrate structures, complex metal hydrides, nanostructured (e.g. carbon) an nanoporous materials. Fundamental studies are necessary to determine the ultimate hydrogen capacity of each system. Nanoporous Metal-organic Framework (MOF) materials are promising candidates for hydrogen storage because the chemical nature and size of their unit cell can be tailored to weakly attract and incorporate H2 molecules, with good volumetric and mass density. In this talk, we consider the structure M2(BDC)2(TED), where M is a metal atom (Zn, Ni, Cu), BDC is benzenedicarboxylate and TED triethylenediamine, to determine the location and interaction of H2 molecules within the MOF. These compounds are isostructural and crystallize in the tetragonal phase (space group P4/ncc), they construct 3D porous structures with relatively large pore size (˜7-8 A ), pore volume (˜0.63-0.84 cc/g) and BET surface area (˜1500-1900 m^2/g). At high pressures (300-800 psi), the perturbation of the H-H stretching mode can be measured with IR absorption spectroscopy, showing a 35 cm-1 redshift from the unperturbed ortho (4155 cm-1 ) and para (4161 cm-1 ) frequencies. Using a newly developed non empirical van der Waals DFT method vdW-DFT),ootnotetextJ.Y. Lee, D.H. Olson, L. Pan, T.J. Emge, J. Li, Adv. Func. Mater. 17, 1255 (2007) it can be shown that the locus of the deepest H2 binding positions lies within to types of narrow channels. The energies of the most stable binding sites, as well as the number of such binding sites, are consistent with the values obtained from experimental adsorption isotherms, and heat of adsorption) data.ootnotetextM. Dion, H. Ryberg, E. Schroder, D. C. Langreth, B.I. Lundqvist, Phys. Rev. Lett. 92, 246401 (2004). Importantly, the

  4. Two-step adsorption on jungle-gym-type porous coordination polymers: dependence on hydrogen-bonding capability of adsorbates, ligand-substituent effect, and temperature.

    Science.gov (United States)

    Uemura, Kazuhiro; Yamasaki, Yukari; Onishi, Fumiaki; Kita, Hidetoshi; Ebihara, Masahiro

    2010-11-01

    A preliminary study of isopropanol (IPA) adsorption/desorption isotherms on a jungle-gym-type porous coordination polymer, [Zn(2)(bdc)(2)(dabco)](n) (1, H(2)bdc = 1,4-benzenedicarboxylic acid, dabco =1,4-diazabicyclo[2.2.2]octane), showed unambiguous two-step profiles via a highly shrunk intermediate framework. The results of adsorption measurements on 1, using probing gas molecules of alcohol (MeOH and EtOH) for the size effect and Me(2)CO for the influence of hydrogen bonding, show that alcohol adsorption isotherms are gradual two-step profiles, whereas the Me(2)CO isotherm is a typical type-I isotherm, indicating that a two-step adsorption/desorption is involved with hydrogen bonds. To further clarify these characteristic adsorption/desorption behaviors, selecting nitroterephthalate (bdc-NO(2)), bromoterephthalate (bdc-Br), and 2,5-dichloroterephthalate (bdc-Cl(2)) as substituted dicarboxylate ligands, isomorphous jungle-gym-type porous coordination polymers, {[Zn(2)(bdc-NO(2))(2)(dabco)]·solvents}(n) (2 ⊃ solvents), {[Zn(2)(bdc-Br)(2)(dabco)]·solvents}(n) (3 ⊃ solvents), and {[Zn(2)(bdc-Cl(2))(2)(dabco)]·solvents}(n) (4 ⊃ solvents), were synthesized and characterized by single-crystal X-ray analyses. Thermal gravimetry, X-ray powder diffraction, and N(2) adsorption at 77 K measurements reveal that [Zn(2)(bdc-NO(2))(2)(dabco)](n) (2), [Zn(2)(bdc-Br)(2)(dabco)](n) (3), and [Zn(2)(bdc-Cl(2))(2)(dabco)](n) (4) maintain their frameworks without guest molecules with Brunauer-Emmett-Teller (BET) surface areas of 1568 (2), 1292 (3), and 1216 (4) m(2) g(-1). As found in results of MeOH, EtOH, IPA, and Me(2)CO adsorption/desorption on 2-4, only MeOH adsorption on 2 shows an obvious two-step profile. Considering the substituent effects and adsorbate sizes, the hydrogen bonds, which are triggers for two-step adsorption, are formed between adsorbates and carboxylate groups at the corners in the pores, inducing wide pores to become narrow pores. Interestingly, such

  5. H2 storage in isostructural UiO-67 and UiO-66 MOFs.

    Science.gov (United States)

    Chavan, Sachin; Vitillo, Jenny G; Gianolio, Diego; Zavorotynska, Olena; Civalleri, Bartolomeo; Jakobsen, Søren; Nilsen, Merete H; Valenzano, Loredana; Lamberti, Carlo; Lillerud, Karl Petter; Bordiga, Silvia

    2012-02-07

    The recently discovered UiO-66/67/68 class of isostructural metallorganic frameworks (MOFs) [J. H. Cavka et al. J. Am. Chem. Soc., 2008, 130, 13850] has attracted great interest because of its remarkable stability at high temperatures, high pressures and in the presence of different solvents, acids and bases [L. Valenzano et al. Chem. Mater., 2011, 23, 1700]. UiO-66 is obtained by connecting Zr(6)O(4)(OH)(4) inorganic cornerstones with 1,4-benzene-dicarboxylate (BDC) as linker resulting in a cubic MOF, which has already been successfully reproduced in several laboratories. Here we report the first complete structural, vibrational and electronic characterization of the isostructural UiO-67 material, obtained using the longer 4,4'-biphenyl-dicarboxylate (BPDC) linker, by combining laboratory XRPD, Zr K-edge EXAFS, TGA, FTIR, and UV-Vis studies. Comparison between experimental and periodic calculations performed at the B3LYP level of theory allows a full understanding of the structural, vibrational and electronic properties of the material. Both materials have been tested for molecular hydrogen storage at high pressures and at liquid nitrogen temperature. In this regard, the use of a longer ligand has a double benefit: (i) it reduces the density of the material and (ii) it increases the Langmuir surface area from 1281 to 2483 m(2) g(-1) and the micropore volume from 0.43 to 0.85 cm(3) g(-1). As a consequence, the H(2) uptake at 38 bar and 77 K increases from 2.4 mass% for UiO-66 up to 4.6 mass% for the new UiO-67 material. This value is among the highest values reported so far but is lower than those reported for MIL-101, IRMOF-20 and MOF-177 under similar pressure and temperature conditions (6.1, 6.2 and 7.0 mass%, respectively) [A. G. Wong-Foy et al. J. Am. Chem. Soc., 2006, 128, 3494; M. Dinca and J. R. Long. Angew. Chem., Int. Ed., 2008, 47, 6766]. Nevertheless the remarkable chemical and thermal stability of UiO-67 and the absence of Cr in its structure would

  6. 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 nitrogen atoms. Lastly, the two-dimensional quantum rotational levels

  7. 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)

    Sun, Jiayin; Zhang, Daojun; Wang, Li; Zhang, Renchun; Wang, Junjie; Zeng, Ying; Zhan, Jinling; Xu, Jianing; Fan, Yong

    2013-01-01

    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), [Zn 1.5 (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 μ 3 -L bridging ligands and Zn(II) ions, which are further linked by pillared 1,4-bdc 2− 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

  8. Kagóme Cobalt(II)-Organic Layers as Robust Scaffolds for Highly Efficient Photocatalytic Oxygen Evolution.

    Science.gov (United States)

    Xu, Jiaheng; Wang, Zhi; Yu, Wenguang; Sun, Di; Zhang, Qing; Tung, Chen-Ho; Wang, Wenguang

    2016-05-23

    Two Kagóme cobalt(II)-organic layers of [Co3 (μ3 -OH)2 (bdc)2 ]n (1) and [Co3 (μ3 -OH)2 (chdc)2 ]n (2) (bdc=o-benzenedicarboxylate and chdc=1,2-cyclohexanedicarboxylate) that bear bridging OH(-) ligands were explored as water oxidation catalysts (WOCs) for photocatalytic O2 production. The activities of 1 and 2 towards H2 O oxidation were assessed by monitoring the in situ O2 concentration versus time in the reaction medium by utilizing a Clark-type oxygen electrode under photochemical conditions. The oxygen evolution rate (RO2 ) was 24.3 μmol s(-1)  g(-1) for 1 and 48.8 μmol s(-1)  g(-1) for 2 at pH 8.0. Photocatalytic reaction studies show that 1 and 2 exhibit enhanced activities toward the oxidation of water compared to commercial nanosized Co3 O4 . In scaled-up photoreactions, the pH value of the reaction medium decreased from 8.0 to around 7.0 after 20 min and the O2 production ceased. Based on the amounts of the sacrificial oxidant (K2 S2 O8 ) used, the yield of O2 produced is 49.6 % for 2 and 29.8 % for 1. However, the catalyst can be recycled without a significant loss of catalytic activity. Spectroscopic studies suggest that the structure and composition of recycled 1 and 2 are maintained. In isotope-labeling H2 (18) O (97 % enriched) experiments, the distribution of (16) O(16) O/(16) O(18) O/(18) O(18) O detected was 0:7.55:92.45, which is comparable to the theoretical values of 0.09:5.82:94.09. This work not only provides new catalysts that resemble ligand-protected cobalt oxide materials but also establishes the significance of the existence of OH(-) (or H2 O) binding sites at the metal center in WOCs. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Biochemical fingerprint and pharmacological applications of Barleria noctiflora L.f. leaves.

    Science.gov (United States)

    Alagar Yadav, Sangilimuthu; Ramalingam, Sathishkumar; Jebamalairaj, Anitha; Subban, Ravi; Sundaram, Karpagavalli Mennakshi

    2016-12-01

    Background Antioxidant and antihistamine agents from Barleria noctiflora L.f. as natural source due to the existing modern medicine give various adverse effects to overcome these problems with natural products. MethodsB. noctiflora leaves extract was fractionated with column chromatography; the homogenized fractions were monitored with thin layer chromatography (TLC) and characterized by using UV-visible, FT-IR, 1H NMR, 13C NMR and mass spectrometry spectral studies. The volatile phytoconstituents of B. noctiflora extract were analysed by gas chromatography-mass spectrometry. Phytoconstituents from B. noctiflora leaves extract were screened for their antioxidant and antihistamine potential in vitro (2,2-diphenyl-1-picrylhydrazyl radical scavenging activity, 2,2'-azinobis-3-ethylbenzothiozoline-6-sulfonic acid radical decolouration assay, nitric oxide radical scavenging activity, superoxide radical scavenging activity and hydrogen peroxide radical scavenging activity) and in silico (molecular docking), respectively. Results Antioxidant and antihistamine barlerinoside has been isolated and characterized from the leaves of B. noctiflora L.f. Barlerinoside revealed their free-radical scavenging ability on OH-, OH•, NO-, O2- and H2O2 radicals and found high percentage inhibition against OH- radical at the IC50 value of 50.45±2.52  µg. The methanol (MeOH) extract of B. noctiflora leaves contains cyclotene; N,N-dimethylglycine; tetrahydrocyclopenta [1,3] dioxin-4-one; phenol, 2-methoxy-; benzofuran, 2-methyl-; 1,4:3,6-dianhydro-α-d-glucopyranose; 2-methoxy-4-vinylphenol; 1,3;2,5-dimethylene-l-rhamnitol; levoglucosan and bicyclo[2.2.2]oct-7-ene-2,5-dione as being the major compounds. Among phytoconstituents present in the extract, the hexestrol; 1,2-benzenedicarboxylic acid, bis(2-methylpropyl) ester; 1-(3,6,6-trimethyl-1,6,7,7a-tetrahydrocyclopenta[c]pyran-1-yl) ethanone; megastigmatrienone; furan interacted with histamine H1 receptor and bind at GLU-177 and ASP

  10. Adsorption and separation of CO{sub 2} on Fe(II)-MOF-74: Effect of the open metal coordination site

    Energy Technology Data Exchange (ETDEWEB)

    Lou, Wolong; Yang, Jiangfeng; Li, Libo; Li, Jinping, E-mail: Jpli211@hotmail.com

    2014-05-01

    We describe the successful synthesis of Fe{sub 2}(dobdc) (dobdc{sup 4−}=2, 5-dioxido-1, 4-benzenedicarboxylate), which has an open metal coordination site Fe(II), and investigate the adsorption properties of three important molecules CO{sub 2}, CH{sub 4} and N{sub 2} on Fe{sub 2}(dobdc) and an oxidized analog, Fe{sub 2}(O{sub 2})(dobdc). We found that CO{sub 2} adsorption isotherm of Fe{sub 2}(dobdc) at 10 bar was very different from Fe{sub 2}(O{sub 2})(dobdc), with the capacities of 144.5 cm{sup 3} g{sup −1} and 98.1 cm{sup 3} g{sup −1}, respectively. The adsorption capacities for CH{sub 4} were 75.8 cm{sup 3} g{sup −1} and 36.8 cm{sup 3} g{sup −1}, respectively, at 10 bar in these materials. Using ideal adsorbed solution theory (IAST), we obtain the adsorption selectivity for CO{sub 2} using equimolar mixtures of CO{sub 2}/CH{sub 4} and CO{sub 2}/N{sub 2} with Fe{sub 2}(dobdc) and Fe{sub 2}(O{sub 2})(dobdc) as a function of pressure. Fe{sub 2}(dobdc) has a higher, more stable separation factor. - Graphical abstract: The selectivity of CO{sub 2}/CH{sub 4} mixture (50%/50%) on Fe{sub 2}(dobdc) and Fe{sub 2}(O{sub 2})(dobdc). - Highlights: • We explored the contrastive adsorption of CO{sub 2}, CH{sub 4}, and N{sub 2} in Fe{sub 2}(dobdc) and Fe{sub 2}(O{sub 2})(dobdc) for the first time. • Through IAST, we obtain the adsorption selectivity for CO{sub 2} from the equimolar mixture of CO{sub 2}/CH{sub 4} and CO{sub 2}/N{sub 2} for Fe{sub 2}(dobdc) and Fe{sub 2}(O{sub 2})(dobdc). • We determined that the open coordination site of Fe(II) is the main reason for different adsorption performances.

  11. Chemical Composition, Antimicrobial and Antioxidant Activities of the Flower Volatile Oils of Fagopyrum esculentum, Fagopyrum tataricum and Fagopyrum Cymosum

    Directory of Open Access Journals (Sweden)

    Jianglin Zhao

    2018-01-01

    Full Text Available The purpose of this study was to investigate the chemical composition and biological activity of the volatile oils (VOs from the flowers of three buckwheat species, Fagopyrum esculentum, Fagopyrum tataricum and Fagopyrum cymosum. The VOs were obtained from the fresh buckwheat flowers by hydrodistillation, and were analyzed for their chemical composition by gas chromatography-mass spectrometry (GC-MS. Nonanoic acid (7.58%, (E-3-hexen-1-ol (6.52%, and benzothiazole (5.08% were the major constituents among the 28 identified components which accounted for 92.89% of the total oil of F. esculentum. 2-Pentadecanone (18.61%, eugenol (17.18%, 1,2-benzenedicarboxylic acid, bis(2-methylpropyl ester (13.19%, and (E,E-farnesylacetone (7.15% were the major compounds among the 14 identified components which accounted for 88.48% of the total oil of F. tataricum. Eugenol (12.22%, (E-3-hexen-1-yl acetate (8.03%, linalool oxide (7.47%, 1-hexanol (7.07%, and benzothiazole (6.72% were the main compounds of the 20 identified components which accounted for 90.23% of the total oil of F. cymosum. The three VOs were screened to have broad spectrum antibacterial activity with minimum inhibitory concentration (MIC values ranged from 100.0 μg/mL to 800.0 μg/mL against the tested bacteria, and their median inhibitory concentration (IC50 values were from 68.32 μg/mL to 452.32 μg/mL. Xanthomonas vesicatoria was the most sensitive bacterium. Moreover, the flower VOs of F. esculentum, F. tataricum and F. cymosum also exhibited noteworthy antioxidant capacity with the IC50 value of 354.15 μg/mL, 210.63 μg/mL, and 264.92 μg/mL for the 1,1-diphenyl-2-picrylhydrazyl (DPPH free radical scavenging assay, and the value of 242.06 μg/mL, 184.13 μg/mL, and 206.11 μg/mL respectively for the β-carotene-linoleic bleaching test. These results suggested the volatile oils of buckwheat flowers could be potential resource of natural antimicrobial and antioxidant agents.

  12. Four thiophene-pyridyl-amide-based Zn{sup II}/Cd{sup II} coordination polymers: Assembly, structures, photocatalytic properties and fluorescent recognition for Fe{sup 3+}

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Xiu-Li; Wu, Xiao-Mei; Liu, Guo-Cheng; Li, Qiao-Min; Lin, Hong-Yan; Wang, Xiang

    2017-05-15

    By tuning metal ions and combining with different dicarboxylates, four new semi-rigid thiophene-bis-pyridyl-bis-amide-based coordination polymers, namely, [Zn(3-bptpa)(1,3-BDC)]·DMA·2H{sub 2}O (1), [Zn(3-bptpa)(5-MIP)] (2), [Cd(3-bptpa)(1,3-BDC)]·2H{sub 2}O (3) and [Cd(3-bptpa)(5-MIP)]·4H{sub 2}O (4) (3-bptpa=N,N′-bis(pyridine-3-yl)thiophene-2,5-dicarboxamide, 1,3-H{sub 2}BDC=1,3-benzenedicarboxylic acid, 5-H{sub 2}MIP=5-methylisophthalic acid, DMA=N,N-dimethylacetamide), were solvothermally/hydrothermally synthesized and structurally characterized by single-crystal X-ray diffraction analyses, IR spectra, UV–vis diffuse-reflectance spectra (DRS), powder X-ray diffraction (PXRD) and thermal gravimetric analyses (TG). The structural analysis reveals that Zn-complexes 1 and 2 are similar 2D networks. While Cd-complexes 3 and 4 exhibit similar 2-fold interpenetrating 3D α-Po frameworks with the (4{sup 12}·6{sup 3}) topology. The photocatalytic properties for the degradation of methylene blue (MB) under ultraviolet light irradiation of the title complexes have been investigated in detail. Furthermore, the luminescent sensing behaviors for metal cations of 1–4 have been studied, the results indicate that 3 is an excellent fluorescent probe, with high sensitivity, selectivity, and simple regeneration, for environmentally relevant Fe{sup 3+} ions. - Graphical abstract: Four Zn{sup II}/Cd{sup II} coordination polymers with a thiophene-pyridyl-amide ligand have been prepared. The photocatalytic activities and fluorescent sensing properties for metal ions of the title complexes have been investigated. - Highlights: • Four coordination polymers with thiophene-pyridyl-amide ligands have been obtained. • The central metal ions play an important role in the formation of the frameworks. • The photoluminescent sensing and the photocatalytic properties have been investigated.