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A novel phthalonitrile derivative bearing 2‐isopropyl‐6‐methylpyrimidin‐4‐yloxy substituents at peripheral positions was synthesized by a nucleophilic substitution reaction. Metallophthalocyanines were obtained from the reaction of the novel phthalonitrile with metal Zn, Cu, Co, and Ni salts. The characterization of the compounds was performed using elemental analysis as well as UV/Vis, FT‐IR, and 1H‐NMR spectroscopy. The aggregation behaviors of phthalocyanine complexes were also investigated. These metallophthalocyanines do not show any aggregation behavior between 10–4–10–6 M concentration range in THF. The antioxidant activities of the synthesized compounds were evaluated using three different tests: 2, 2‐diphenyl‐1‐picrylhydrazyl (DPPH) radical scavenging, metal chelating activity, and reducing power assays. All the compounds exhibited various antioxidant activities. In addition, antimicrobial activity of the compounds was tested over four gram positive and two gram negative bacteria. Moreover, the ground‐state geometries of the complexes were optimized using density functional theory (DFT) methods at B3LYP/6‐31G(d, p) level in order to obtain information about the 3D arrangements and electronic structure.  相似文献   
2.
Four metal complexes, IL-OPPh2-Ru-p-cymene (3) , IL-OPPh2-Ru-benzene (4) , IL-OPPh2-Ir-Cp* (5) , IL-OPPh2-Rh-COD (6) , have been evaluated for in vitro antioxidant activity such as 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging and reducing power activity. Maximum scavenging activity (71.43%) was obtained with IL-OPPh2-Ru-p-cymene, whereas IL-OPPh2-Rh-COD showed the highest reducing power ability. The complexes were also studied for their antimicrobial activity against three Gram-positive and three Gram-negative bacteria. In addition, DNA binding of the complexes was evaluated using calf thymus DNA. Both Ru(II) complexes exhibited good DNA-binding activity while the other complexes did not have any activity. Furthermore, ab initio quantum calculations of four complexes were also carried out using density functional theory to better understand their chemical behaviors.  相似文献   
3.
JPC – Journal of Planar Chromatography – Modern TLC - Simultaneous High-Performance Thin-Layer Chromatographic Determination of Indole Acetic Acid, Indole Butyric Acid, and Absisic Acid...  相似文献   
4.
4, 4′‐(1, 4‐Phenylenebis(oxy)diphthalonitrile was synthesized by reaction of hydroquinone with 4‐nitrophthalonitrile. Binuclear metallophthalocyanines 2–4 were obtained by the reaction between 4, 4′‐(1, 4‐phenylenebis(oxy)diphthalonitrile and 4‐(benzo [d] 1 , 3 dioxol‐5‐ylmethoxy)phthalonitrile in the presence of metal salts. These new compounds were characterized by using elemental analysis, FTIR, 1H‐NMR and UV/Vis spectroscopic data. Thermal properties of phthalocyanines 2‐4 were investigated by TG and DTA. In addition, antioxidant properties of compounds II , 3 and 4 were investigated. Their radical‐scavenging capacity and chelating effects was fully studied. The maximum 1, 1‐diphenyl‐2‐picrylhydrazyl radicals (DPPH) were obtained from compound 3 . Chelating effects on ferrous ions were 91.6 % at concentration of 100 mg L–1 with compound II .  相似文献   
5.
This review (160 refs). covers the current state of the art of microbacteria-based sorbents for preconcentration of metal ions at trace levels. We highlight advantages and major challenges of the techniques and discuss future perspectives of both batch and column-based methods. Particular attention is paid to the preconcentration of metal ions using resin-immobilized microbacteria for solid phase extractions. We also discuss detection methods including UV–vis spectrophotometry, FAAS, ICP-OES and ICP-MS. Analytical figures of merit are compared, and examples are given for the application to a variety of samples including food, beverages, alloys, water, soil, and geological samples.
Figure
An graphical presentation of main experimental steps in solid phase extraction procedure for metal ions together with the summarization of affinity of metal ions to functional groups on the surface of bacteria by considering the classifications according to hard and soft acids and bases theory by Pearson  相似文献   
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7.

Abstract  

Visualization of large volumetric datasets has always been an important problem. Due to the high computational requirements of volume-rendering techniques, achieving interactive rates is a real challenge. We present a selective refinement scheme that dynamically refines the mesh according to the camera parameters. This scheme automatically determines the impact of different parts of the mesh on the output image and refines the mesh accordingly, without needing any user input. The view-dependent refinement scheme uses a progressive mesh representation that is based on an edge collapse-based tetrahedral mesh simplification algorithm. We tested our view-dependent refinement framework on an existing state-of-the-art volume renderer. Thanks to low overhead dynamic view-dependent refinement, we achieve interactive frame rates for rendering common datasets at decent image resolutions.  相似文献   
8.
Two cis-1,2-diol-type chiral ligands (T 1 and T 2 ) and their tri-coordinated chiral dioxaborinane (T (1–2) B (1–2) ) and four-coordinated chiral dioxaborinane adducts with 4-tert-butyl pyridine sustained by N → B dative bonds (T (1–2) B (1–2) -N) were synthesized and characterized by various spectroscopic techniques such as NMR (1H, 13C, and 11B), FT-IR and UV–Vis spectroscopy, LC–MS/MS, and elemental analysis. It was suggested that both ferrocene and trifluoromethyl groups played key roles in the catalytic and biological studies because they could tune the solubility of the chiral dioxaborinane complexes and adjust the strength of intermolecular interactions. To assess the biological activities of newly synthesized chiral dioxaborinane compounds, DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging, reducing power, antibacterial, DNA binding, and DNA cleavage activities were tested. Then, all chiral dioxaborinane complexes were investigated as catalysts for the asymmetric transfer hydrogenation of various ketones under suitable conditions. The results indicated that the chiral dioxaborinane catalysts performed well with high yields.  相似文献   
9.
Schiff base derivatives with anthracene- and pyrene-based units, A1-A6 and P1-P6 were synthesized (89%–99% yields). Schiff base derivatives were designed to possess an heterocyclic moiety on one side to enhance the coordination ability towards metals. To investigate the biological assay of the newly synthesized compounds, their DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging, metal chelating, reducing power, antibacterial and DNA binding activities were tested. A6 (63.1%) showed the maximum free radical scavenging activity among all. However, compound P3 at concentration of 200 μg/mL possessed the highest metal chelating (45.8%) activity and power of reduction. In addition, P3 and A6 showed antibacterial activity against all bacteria tested and both compounds were very well bound to CT-DNA. Density functional theory method with B3LYP/6-311++G(d,p) basis set was performed to get information about the structural and electronic properties of the present compounds. In addition, the metal coordination properties of the dimers of the parent Schiff bases were investigated through interactions with Zn2+.  相似文献   
10.
Coriolus versicolor, a wood fungus, was immobilised on Amberlite XAD-4 and used as solid-phase biosorbent for preconcentrations of rare earth elements. La(III), Th(IV), U(IV) and Ce(III) were subjected to solid-phase extraction procedure. We observed that La(III) was selectively preconcentrated, while other ions remained in solution at pH 6.0. 5.0 mL of 1.0 mol L?1 HCl was used to elaute La(III) from column. 250 mg of C. versicolor loaded on 1000 mg of XAD-4 was optimised as solid-phase matrix. Concentrations of ions in solutions were determined by inductively coupled plasma– optical emission spectrometry (ICP-OES). The calibration plot after preconcentration was linear in the range from 1.0 to 50.0 ng mL?1 for La(III). Limit of detection was found as 0.27 ng mL?1 for La(III) by SPE method. Relative standard deviation was found lower than 6.7% for 1.0 ng mL?1 of La(III) solution (n = 10). The sensitivity of ICP-OES was improved by a factor of 46.8. The applicability of the method was validated through the analysis of certified reference samples of tea (NCS ZC-73014) and spinach (NCS ZC-73013).  相似文献   
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