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1.
Reactions of Zn(II) salts, 5-(4-(1H-imidazol-1-yl)phenyl)-1H-tetrazolate (HIPT) and 2-mercaptobenzoic acid or 2-propyl-1H-imidazole-4,5-dicarboxylic acid (H3PrIDC), result in two mixed-ligand coordination polymers (CPs), [Zn2(IPT)(DSDB)(OH)]n (H2DSDB = 2,2′-disulfanediyldibenzoic acid, 1) and [Zn2(IPT)(PrIDC)(H2O)]n (H3PrIDC = 2-propyl-1H-imidazole-4,5-dicarboxylic acid, 2). Compound 1 possesses a 2-D structure built by 1-D [Zn(IPT)]n chains and DSDB2? connectors, in which the DSDB2? is generated via in situ reaction from 2-mercaptobenzoic acid. It displays a new intricate 4-nodal {3·4·6·7·8·9}{3·6·7·8·9·10}{3·8·9}{4·6·8} topology. Compound 2 displays a 3-D framework with new 3-connected topology with Schläfli symbol of (4·8·10) (8·122), in which the 1-D Zn-carboxylate chains were bridged by 3-connected IPT? ligands. The thermal stabilities and luminescence properties of 1 and 2 have also been studied. The compounds exhibit intense solid-state fluorescent emissions at room temperature.  相似文献   

2.
Various adsorbent materials have been reported in the literature for protein separation. We have developed a novel and new approach to obtain high protein‐adsorption capacity utilizing a 2‐methacrylamidoalanine‐containing membrane. An amino acid ligand 2‐methacrylamidoalanine (MAAL) was synthesized from methacrylochloride and alanine. Then, poly[(2‐hydroxyethyl methacrylate)‐co‐(2‐methacrylamidoalanine)] [p(HEMA‐co‐MAAL)] membranes were prepared by UV‐initiated photopolymerization of HEMA and MAAL. The synthesized MAAL monomer was characterized by NMR spectrometry. p(HEMA‐co‐MAAL) membranes were characterized by swelling studies, porosimeter, scanning electron microscopy, FT‐IR spectroscopy and elemental analysis. These membranes have large pores; the micropore dimensions are around 5–10 μm. p(HEMA‐co‐MAAL) affinity membranes with a swelling ratio of 198.9%, and containing 23.9 (mmol MAAL)·m–2 were used in the adsorption of lysozyme from aqueous media containing different amounts of lysozyme (0.1–3.0 mg·ml–1) and at different pH values (4.0–8.0). The effect of Cu(II) incorporation on lysozyme adsorption was also studied. The non‐specific adsorption of lysozyme on the pHEMA membranes was 0.9 μg‐cm–2. Incorporation of MAAL molecules into the polymeric structure significantly increased the lysozyme adsorption up to 2.96 mg·cm–2. The lysozyme‐adsorption capacity of the membranes incorporated with Cu(II) (9.98 mg·cm–2) was greater than that of the p(HEMA‐co‐MAAL) membranes. More than 85% of the adsorbed lysozyme was desorbed in 1 h in the desorption medium containing 1.0 M NaCl. The p(HEMA‐co‐MAAL) membranes are suitable for repeated use for more than 5 cycles without noticeable loss of capacity. These features make p(HEMA‐co‐MAAL) membrane a very good candidate for bioaffinity adsorption.  相似文献   

3.
《Analytical letters》2012,45(7-8):1367-1376
The voltammetric behavior of epinephrine was investigated by differential pulse voltammetry (DPV) at a carbon paste electrodes (CPE) made of different carbon powders – CR-2, glassy carbon (GC) microparticles, and single-wall carbon nanotubes (SWNT). In Briton-Robinson (BR) buffer solution pH 6, the linear dependence was found for the determination of epinephrine by the given method in the concentration ranges of 1·10?6–1·10?4 (CR-2), 1·10?6–1·10?4 (GC microparticles) and 4·10?6–1·10?4 (SWNT) mol·dm?3. Limits of detection were 8·10?7, 8·10?7, and 2·10?6 mol·dm?3, respectively. The best results were obtained employing CPE containing carbon paste with 50% (m/m) of SWNT, a linear dynamic range being 4·10?7–1·10?4 mol·dm?3 and a limit of detection 2·10?7 mol·dm?3. The attempt to increase the sensitivity by adsorptive accumulation of epinephrine was not successful.  相似文献   

4.
Two new coordination polymers, namely [Zn3(1,3,5-BTC)2(L1)2(H2O)2] · 2H2O (1) and [Cd3(1,2,3-BTC)2(L2)3] · H2O (2) (where L1 = 1,2-bis(imidazol-1-ylmethyl)benzene, L2 = 1,1′-(1,4-butanediyl)bis(imidazole), 1,3,5-H3BTC = 1,3,5-benzenetricarboxylic acid and 1,2,3-H3BTC = 1,2,3-benzenetricarboxylic acid), were synthesized in hydrothermal conditions. In 1, each 1,3,5-BTC anion coordinates to three Zn cations, and the framework of 1 can be simplified as (6 · 8 · 10)2(62 · 8 · 103)(82 · 10)(62 · 10) topology. In 2, 1,2,3-BTC anions coordinate to three cadmiums, and the whole structure displays a (62 · 84)2(64 · 8 · 10)(62 · 8)2 network containing three different types of nodes. The luminescent properties for 1 and 2 are discussed.  相似文献   

5.
Two novel three-dimensional (3-D) coordination polymers, [Pb(HTDA)] n (1) and [Co5(TDA)2(H2TDA)2(H2O)8] n (2) [H3TDA = 1H-1,2,3-triazole-4,5-dicarboxylic acid], have been prepared by hydrothermal reactions and characterized by elemental analysis, infrared spectroscopy and single-crystal X-ray diffraction. Compound 1 is constructed from rod-shaped secondary building units (SBUs) and exhibits a 3-D network with (410·65)(410·63·82) topology. Compound 2 is built up from ligands bridging three different cobalt ions and exhibits a 3-D network with (4·82)3(4·82·103) topology. In addition, the thermal stabilities of the two compounds, the photoluminescence properties of compound 1 and the magnetic properties of compound 2 have been studied.  相似文献   

6.
Two new complexes based on 4,4′-[1,3-phenylenebis(oxy)]diphthalic acid (H4L) ligands were synthesized, namely, [Cd2(L)(1,10-phen)2(H2O)]n( 1 ) and [Co2(L)(1,10-phen)2(H2O)]n( 2 ), in which 2D structures transform into 3D supramolecular structures by C H···π interaction. The proton conductivity of complexes 1 and 2 at low temperature is close (σ1 = 3.12 × 10−8 S cm−1 and σ2 = 3.81 × 10−8 S cm−1 at 30°C), but these two complexes show different conduction mechanisms. The Vehicular mechanism in 1 is caused by the O···H/H···O contact in 1 , which is stronger than 2 , and the Grotthuss mechanism in 2 is caused by the N···H/H···N contact in 2 , which is stronger than 1 . At the same time, complex 1 showed excellent antibacterial properties in vitro, mainly reflected in that five kinds of bacteria (Escherichia coli, Bacillus amyloliquefaciens, Pantoea agglomerans, Pseudomonas putida, and Pectobacterium carotovora) could play an obvious inhibitory effect in the concentration range of 20 μg·ml−1.  相似文献   

7.
Pulse radiolysis has been used to investigate the reaction of hydroxyl radical (·OH) and oxide radical anion (O·−) with 2-aminopurine (2AP), a fluorescent analogue of adenine, in aqueous medium. The second-order rate constant for the reaction of ·OH with 2AP was determined to be 3 × 109 dm3 mol−1s−1 and for the reaction of O·− it was 7.1 × 108 dm3 mol−1s−1. The transient absorption spectrum obtained in the reaction of ·OH at pH 7 has absorption maxima at 370 and 470 nm. The spectrum undergoes a time-dependent transformation at higher time-scale. The intermediate species was found to react with N,N,N′,N′-tetramethyl-p-phenylenediamine (TMPD). The yield of TMPD·+ was calculated in terms of G(TMPD·+) to be 3.3 × 10−7 mol J−1 at pH 7. The ·OH reactions were also carried out at pH 10 and the transient absorption spectra have λ max at 400 and 480 nm. The transient spectra obtained in the reaction of O·− at pH ≈14 have maxima at 400 and 480 nm. The transient intermediate species at pH 7 are assigned to the formation of 2AP-4-OH· (54%), 2AP-5-OH· (7%) and 2AP-8-OH· (39%) based on the spectral evidence and TMPD·+ build-up. Both 2AP-4-OH· and 2AP-5-OH· undergo OH elimination to form a radical cation. At higher pH (pH 10), the dehydration reaction of these OH-adducts leads to a N-centered radical (2AP-N(9)·, 71%). Formation of 2AP-8-OH· (29%) is also proposed at this pH. In the reaction of O·− with 2AP, it is proposed that a similar nitrogen centered 2AP-N(9)· radical is formed by an electron-transfer reaction at N(9).  相似文献   

8.
In the presence of Cu(II) ions, a chiral rare earth iodate Gd(IO3)3?·?H2O (crystallizing in P21 (no. 4) space group), was synthesized hydrothermally from Gd2O3 and HIO3; the structure is the topologically (3,?8)-connected (43)(4?·?62)(49?·?617?·?82) network, constructed from 3-connected trigonal nodes (I1, I3) and 8-connected tetragonal prism nodes (Gd1).  相似文献   

9.
A new Cd-MOF containing the nucleobase adenine and multicarboxylates, Cd2(tdc)2(1H-ade)2(H2O) (H2tdc = 2,5-thiophene carboxylic acid, 1H-ade = adenine), was synthesized successfully under hydrothermal condition and characterized by single-crystal X-ray diffraction, infrared spectrum, thermogravimetric analysis and photoluminescence. The two crystallographically unsymmetrical Cd atoms are bridged by 2,5-tdc ligands with (κ11)-(κ1)-μ3 and (κ1–κ1)–μ2 modes into two dimensional extended layers, which are further pillared with the neutral ade molecules to form a 3D frameworks stabilized by extensive π ··· π interactions between imidazole-, pyrimidine- and thiophene-rings. Inspection of the structure reveals that the architecture can be simplified as a 3,4,5- connected networks with a Schläfli symbol of (62 · 8)(42 · 63 · 8)(42 · 65 · 83). The photochemical property shows that the luminescent emission can be significantly quenched by aromatic azo compounds. The quenching effect coefficient (Ksv) for bis(4-imidazol-1-yl-phenyl)diazene is determined to be 4.1 × 104 m –1, indicating the title compound as a potential fluorescent sensing materials.  相似文献   

10.
The oxidation of Na4Fe(CN)6 complex by S2O anion was found to follow an outer‐sphere electron transfer mechanism. We firstly carried out the reaction at pH=1. The specific rate constants of the reaction, kox, are (8.1±0.07)×10?2 and (4.3±0.1)×10?2 mol?1·L·s?1 at μ=1.0 mol·L?1 NaClO4, T=298 K for pH=1 (0.1 mol·L?1 HCl04) and 8, respectively. The activation parameters, obtained by measuring the rate constants of oxidation 283–303 K, were ΔH=(69.0±5.6) kJ·mol?1, ΔS=(?0.34±0.041)×102 J·mol?1·K?1 at pH=l and ΔH=(41.3±5.5) kJ·mol?1, ΔS=(?1.27±0.33)×102 J·mol?1·K?1 at pH=8, respectively. The cyclic voltammetry of Fe(CN) shows that the oxidation is a one‐electron reversible redox process with E1/2 values of 0.55 and 0.46 V vs. normal hydrogen electrode at μ=1.0 mol·L?1 LiClO4, for pH=1 and pH=8 (Tris). respectively. The kinetic results were discussed on the basis of Marcus theory.  相似文献   

11.
The crystalline complex ImH[CuCl2(HOCH2C≡CCH2OH)] has been synthesized by the direct interaction of 2-butyne-1,4-diol with CuCl in concentrated aqueous solution of (ImH)Cl (ImH+ is imidazolium cation) and studied by X-ray crystallography. The crystals are triclinic, space group P $\overline 1 $ , a = 7.08(2) Å, b = 7.49(1) Å, c = 10.962(8) Å, α = 101.76(8)°, β = 95.85(8)°, γ = 99.57(8)°, Z = 2. The structure consists of stacks of discrete anions [CuCl2(HOCH2C≡CCH2OH)]? arranged along the [100] axis and [ImH]+ cations occupying the free space. The environment of π-coordinated Cu(I) atoms is trigonal and consists of two chlorine atoms and the C≡C bond of 2-butyne-1,4-diol molecule. The alcohol groups do not participate in the coordination, but they form strong hydrogen bonds N-H···O (H···O, 1.76(6) Å) and O-H···Cl(H···Cl, 2.29(5) Å).  相似文献   

12.
Reactions of copper(I) halides (Cl, Br, I) with 1‐methyl‐1, 3‐imidazoline‐2‐thione (mimzSH) in 1 : 2 molar ratio yielded sulfur‐bridged dinuclear [Cu2X2(μ‐S‐mimzSH)21‐S‐mimzSH)2] (X = I, 1 , Br, 2 ; Cl, 3 ) complexes. Copper(I) iodide with 1,3‐imidazoline‐2‐thione (imzSH2) and Ph3P in 1 : 1 : 1 molar ratio has also formed a sulfur‐bridged dinuclear [Cu2I2(μ‐S‐imzSH2)2(PPh3)2] ( 4 ) complex. The central Cu(μ‐S)2Cu cores form parallelograms with unequal Cu–S bond distances {2.324(2), 2.454(3) Å} ( 1 ); {2.3118(6), 2.5098(6) Å} ( 2 ); {2.3075(4), 2.5218(4) Å} ( 3 ); {2.3711(8), 2.4473(8) Å} ( 4 ). The Cu···Cu separations, 2.759–2.877Å in complexes 1 – 3 are much shorter than 3.3446Å in complex 4 . The weak intermolecular interactions {H2CH···S# ( 2 ); CH···Cl# ( 3 ); NH···I# ( 4 )} between dimeric units in complexes 2 – 4 lead to the formation of linear 1D polymers.  相似文献   

13.
A novel [Ru(bpy)2(dcbpy)NHS] labeling/aptamer‐based biosensor combined with gold nanoparticle amplification for the determination of lysozyme with an electrochemiluminescence (ECL) method is presented. In this work, an aptamer, an ECL probe, gold nanoparticle amplification, and competition assay are the main protocols employed in ECL detection. With all the protocols used, an original biosensor coupled with an aptamer and [Ru(bpy)2(dcbpy)NHS] has been prepared. Its high selectivity and sensitivity are the main advantages over other traditional [Ru(bpy)3]2+ biosensors. The electrochemical impedance spectroscopy (EIS) and atomic force microscopy (AFM) characterization illustrate that this biosensor is fabricated successfully. Finally, the biosensor was applied to a displacement assay in different concentrations of lysozyme solution, and an ultrasensitive ECL signal was obtained. The ECL intensity decreased proportionally to the lysozyme concentration over the range 1.0×10?13–1.0×10?8 mol L?1 with a detection limit of 1.0×10?13 mol L?1. This strategy for the aptasensor opens a rapid, selective, and sensitive route for the detection of lysozyme and potentially other proteins.  相似文献   

14.
Two manganese(II) coordination polymers, namely, [Mn1.5(BCB)(bpy)1.5(H2O)]n ( 1 ), and [Mn(HBCB)(bibp)2(H2O)] ( 2 ), were assembled from the mixed ligands of the flexible tripodal ligand of 3,5‐bis(2‐carboxylphenoxy)benzoic acid (H3BCB) and two rigid N‐donors [bpy = 4,4′‐bipyridine, and bibp = 4,4′‐bis(imidazolyl)biphenyl]. Their structures were determined by single‐crystal X‐ray diffraction analyses and further characterized by elemental analyses (EA), IR spectra, powder X‐ray diffraction (PXRD), and thermogravimetric (TG) analyses. Structural analysis reveals that complex 1 is a 3D (3,4,6)‐connected {5 · 62}2{56 · 64 · 7 · 82 · 92}{64 · 8 · 9} net based on two kinds of inorganic nodes of dinuclear {Mn2(COO)2} SBUs and Mn(2) ions. Complex 2 is a hydrogen bonds based 3D supramolecule with 6‐connected {412 · 63}‐ pcu net. Besides, the variable‐temperature susceptibilities of 1 and 2 were investigated.  相似文献   

15.
Dichloro(N,N-diethyl-ethane-1,2-diamine)copper(II) has copper(II) ions in square pyramidal coordination. The two nitrogen atoms of the diamine {Cu–Nprimary?=?1.979(3), Cu–Ntertiary?=?2.108(2)?Å} and two chloride ions are in the basal plane {Cu–Cl1?=?2.2680(9), Cu–Cl2?=?2.2989(8)?Å}. A centrosymmetrical dimer di-μ-chloro-bis{chloro(N,N-diethylethane-1,2-diamine-κ2)copper(II)}, C6H16Cl2CuN2, is formed by axial coordination by Cl2, trans to the tertiary nitrogen, to a second copper(II) ion, with Cu?···?Cui?=?3.4855(9) and Cl2–Cui?=?2.7860(8)?Å. The dimer is also linked by H-bond N1–H?···?Cl1i.  相似文献   

16.
In this paper, we have illustrated the utilisation of a second-sphere coordination approach to construct supramolecular inclusion solids with varieties of guest molecules. A flexible molecule N,N,N′,N′-tetra-p-methylbenzyl-ethylenediamine (L1) bearing doubly protonated H-bond donors was designed, capable of forming N–H…Cl hydrogen bonds with a crystallographically unique chloride anion, to construct an anion-directed ligand. The pillared double-layered host framework was constructed by an anion-directed ligand and primary coordination sphere [CoCl4]2 ?  through weak C–H…Cl hydrogen-bonding interactions. A variety of guest molecules, such as p-anisaldehyde, 1,4-dimethoxy-2,5-bis(methoxymethyl)benzene, can be included, leading to the formation of novel supramolecular inclusion solids: [L1]·4[H]+·[CoCl4]2 ? ·2Cl·1.5[C8H8O2]·0.25[CH3OH] (1) and [L1]·4[H]+·[CoCl4]2 ? ·2Cl·1.5[C12H20O4]·0.5[CH3OH] (2).

We have presented herein the utilisation of a second-sphere coordination approach to construct supramolecular inclusion solids with a variety of guest molecules. A novel type of a pillared double-layered host framework was constructed by a second-sphere coordination between the anion-directed ligand (L1 = N,N,N′,N′-tetra-p-methylbenzyl-ethylenediamine) and [CoCl4]2 ?  through weak C–H…Cl hydrogen-bonding interaction, and a variety of guest molecules, such as p-anisaldehyde, 1,4-dimethoxy-2,5-bis(methoxymethyl)benzene, can be included, leading to the formation of supramolecular inclusion solids: [L1]·4[H]+·[CoCl4]2 ? ·2Cl·1.5[C8H8O2]·0.25[CH3OH] (1) and [L1]·4[H]+·[CoCl4]2 ? ·2Cl·1.5[C12H20O4]·0.5[CH3OH] (2)

  相似文献   

17.
Seven new bi‐ and polyhomonuclear transition metal complexes with three polyhydroxlated bisazodianil ligands were synthesized and characterized. The ligands were derived from condensation of 6‐(5‐formyl‐2‐hydroxyphenylazo)‐2,4‐dihydroxypyrimidine with aliphatic diamines (H8L1, H8L2 and H6L3). The data of elemental and thermal analyses, molar conductance measurement, IR, electronic and ESR spectra as well as magnetic moment measurements support the formation of [L1Co7Cl6(H2O)10]·22H2O ( 1 ), [H2L2Mn6Cl6(H2O)8]·3H2O·2EtOH ( 3 ), [L2Co8Cl8(H2O)12]·24H2O ( 4 ), [H4L3Co2Cl2(H2O)2]·8H2O·2EtOH ( 6 ) with a tetrahedral geometry and [H2L1Ni5Cl4(H2O)16]·19H2O·EtOH ( 2 ), [L2Ni8Cl8(H2O)28]·8H2O·EtOH ( 5 ) with an octahedral geometry while [H6L3Cu3(H2O)7]Cl3·10H2O ( 7 ) has a distorted tetrahedral arrangement. The mode of bonding between the metal ions and the ligand molecules is determined and the metal‐metal interaction was studied. The activation thermo‐kinetic parameters for the thermal decomposition steps of the complexes E*, ΔH*, ΔS*, and ΔG* were calculated.  相似文献   

18.
A silver(I) coordination polymer with mixed 2,3,5,6‐tetrachloro‐1,4‐benzenedicarboxylate (BDC‐Cl4) and 2,2′‐bipyridine (2,2′‐bpy) ligands, [Ag2(BDC‐Cl4)(2,2′‐bpy)]n ( 1 ), was synthesized and structurally characterized. Compound 1 features a robust three‐dimensional (3D) network, exhibiting a new (4,6)‐connected net with the Schläfli symbol of (32 · 42 · 5 · 6)2(32 · 42 · 52 · 87 · 9 · 10). The photoluminescence properties of 1 were investigated in the solid state at room temperature.  相似文献   

19.
Abstract. The 3D cobalt(II) coordination polymers [Co1.5(HDDB)(1,4‐bib)1.5(H2O)]n ( 1 ), and {[Co2(DDB)(1,3‐bib)22‐H2O)] · H2O}n ( 2 ) were assembled by mixed‐ligand synthetic strategy [H4DDB = 1,3‐bis(2,4‐dicarboxyphenyl) benzene, 1,3‐bib = 1,3‐bis(1H‐imidazol‐4‐yl)benzene, and 1,4‐bib = 1,4‐bis(1H‐imidazol‐4‐yl)benzene]. Their structures were determined by single‐crystal X‐ray diffraction analyses and further characterized by elemental analyses (EA), IR spectroscopy, powder X‐ray diffraction (PXRD), and thermogravimetric (TG) analyses. Single X‐ray diffraction analysis reveals that complex 1 is an interestingly 3D (3,3.6)‐connected (63)4(65 · 88 · 102) net, and complex 2 is an unprecedented dinuclear [Co2(COO)(μ2‐H2O)] SBUs based 3D (3,6)‐connected (3 · 6 · 7)(32 · 43 · 54 · 63 · 7 · 82) net. Additionally, the magnetic properties of 2 were investigated.  相似文献   

20.
A 3-D metal-organic framework [Cd3(L)2(DMF)2]?·?2H2O?·?2DMF (1) (H3L?=?2-(dimethylcarbamoyl)biphenyl-5,2′,5′-tricarboxylic acid, DMF?=?N,N-dimethylformamide) with trinuclear Cd(II) units has been prepared. Complex 1 is a (3,?6)-connected (42?·?6)2(44?·?62?·?88?·?10) coordination net, which results from the solvothermal in situ formation of a new asymmetric ligand, 2-(dimethylcarbamoyl)biphenyl-5,2′,5′-tricarboxylic acid (H3L), through amidation of biphenyl-2,5,2′,5′-tetracarboxylic acid (H4bptc). Additionally, the luminescence of 1 has been investigated.  相似文献   

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