scholarly journals Iron(IV) Complexes with Tetraazaadamantane-based Ligands: Synthesis, Structure, Application in Dioxygen Activation and Labeling of Biomolecules

2021 ◽  
Author(s):  
Ivan Golovanov ◽  
Anton Leonov ◽  
Vladislav Lesnikov ◽  
Evgeny Pospelov ◽  
Kirill Frolov ◽  
...  
Keyword(s):  
Aerobic Oxidation ◽  
Dioxygen Activation ◽  
Excellent Performance ◽  
Cage Structure ◽  
X Ray ◽  
Polystyrene Matrix ◽  
Oxidase Enzyme ◽  
Ft Ir ◽  
Thiol Oxidase ◽  
First Time

4,6,10-Trihydroxy-1,4,6,10-tetraazaadamantane (TAAD) has been shown to form a stable Fe(IV) complex having a diamantane cage structure, in which the metal center is coordinated by three oxygen atoms of the deprotonated ligand. The complex was characterized by X-ray, HRMS, NMR, FT-IR, Mössbauer spectroscopy and DFT calculations, which supported d4 configuration of iron. The Fe(IV)-TAAD complex showed excellent performance in dioxygen activation under mild conditions serving as a mimetic of the thiol oxidase enzyme. The nucleophilicity of the bridge-head nitrogen atom in TAAD provides a straightforward way for conjugation of Fe(IV)-TAAD complexes to various functional molecules. Using this approach, steroidal and peptide molecules having an iron(IV) label have been prepared for the first time. Also, the Fe(IV)-TAAD complex was covalently bounded to a polystyrene matrix and the resulting material was shown to serve as a heterogeneous catalyst for aerobic oxidation of thiols to disulfides.

scholarly journals Synthesis of new bimetallic phosphate (Al/Ag3PO4) and study for its Catalytic performance in the synthesis of 1,2-dihydro-l-phenyl-3H-naphth [1,2-e]-[1,3] oxazin-3-one derivatives

2021 ◽  
Vol 11 (3) ◽  
pp. 215
Author(s):  
Achraf El Hallaoui ◽  
Tourya Ghailane ◽  
Soukaina Chehab ◽  
Youssef Merroun ◽  
Rachida Ghailane ◽  
...  
Keyword(s):  
Reaction Times ◽  
Catalytic Performance ◽  
X Ray Diffraction ◽  
One Pot ◽  
X Ray ◽  
Silver Sulfate ◽  
Triple Super Phosphate ◽  
Aryl Aldehyde ◽  
Ft Ir ◽  
First Time

<p>This work aims to prepare a new bimetallic phosphate catalyst using a new simple and effective method. This new catalyst was ready for the first time by a modification of Triple Super Phosphate (TSP) fertilizer with silver sulfate (AgSO<sub>4</sub>), followed by the impregnation of the aluminum atoms using aluminum nitrate (Al(NO<sub>3</sub>)<sub>3</sub>). The use of Al/Ag<sub>3</sub>PO<sub>4</sub>, for the first time as a heterogeneous catalyst in organic chemistry, offers a new, efficient, and green pathway for synthesizing 1,2-dihydro-l-phenyl-3H-naphth[1,2-e]-[1,3]oxazin-3-one derivatives by one-pot three-component cyclocondensation of b-naphthol, aryl aldehyde, and urea. The structure and the morphology of the prepared catalyst were characterized by spectroscopic methods such as X-Ray Diffraction (XRD), Fourier Transform Infrared spectroscopy (FT-IR), and dispersive X-ray spectrometry coupled with a scanning electron microscope (EDX-SEM). In addition, the optimization of the reaction parameters was carried out considering the effect of catalyst amount, the temperature, and the solvent. The procedure described herein allowed a comfortable preparation of oxazine derivatives with excellent yields, short reaction times, and in the absence of organic solvent.</p>

Preparation of New Anti-Slip Flooring Coatings: Hydrophobic MMA Floor Coatings

2013 ◽  
Vol 721 ◽  
pp. 73-76
Author(s):  
Shu Le Lin ◽  
Hui Hua Cai
Keyword(s):  
Electronic Spectroscopy ◽  
Dynamic Contact ◽  
Contact Angles ◽  
Coating Properties ◽  
Hydrophobic Properties ◽  
X Ray ◽  
H Nmr ◽  
Potential Applications ◽  
Ft Ir ◽  
First Time

For the first time, hydrophobic MMA floor coatings were prepared based on the fluorine-containing methacrylic ester copolymers and applied as a new kind of anti-slip flooring coatings. The composition of the synthesized copolymers was characterized by FT-IR and 1H-NMR. The prepared hydrophobic MMA floor coatings were analyzed for their coating properties. The hydrophobic properties of the coatings were characterized by static and dynamic contact angles and X-ray photo-electronic spectroscopy (XPS). Results show that the newly prepared floor coatings are easy to apply and have excellent mechanical and hydrophobic properties, which indicates that the hydrophobic MMA floor coatings have great potential applications in anti-slip flooring coatings.

scholarly journals A Novel Cd(II) Isophthalate Complex with Triethanolamine: Crystal Structure, Fluorescence and Antimicrobial Activity

2021 ◽  
Vol 68 (2) ◽  
pp. 466-474
Author(s):  
Zuhal Yolcu ◽  
Sinem Yurtcan ◽  
Meryem Çıtlakoğlu
Keyword(s):  
Antimicrobial Activity ◽  
Room Temperature ◽  
Diffusion Method ◽  
Gram Negative Bacteria ◽  
Single Crystal Diffraction ◽  
X Ray ◽  
Ft Ir ◽  
First Time ◽  
Trigonal Prismatic

A mixed ligand Cd(II) complex [Cd(IsoPht)(TEA)H2O]·3H2O was synthesized for the first time by using isophthalic acid (H2IsoPht) and tetradentate triethanolamine (TEA) and characterized by X-ray single-crystal diffraction, FT-IR, and thermogravimetric analysis (TGA). This novel complex crystallizes in the triclinic system with P-1 space group and distorted monocapped trigonal prismatic geometry. The Cd(II) has seven coordinates with bidentate IsoPht, a TEA in the tetradentate mode, and an aqua ligand. The fluorescence properties of the Cd(II) complex and TEA ligand were investigated at room temperature. The present Cd(II) complex was also tested for its antimicrobial activity by in vitro agar diffusion method against some Gram-positive and Gram-negative bacteria and a fungus.

Cobalt(II), copper(II), and iron(II) tetrasulfophthalocyanines covalently supported on wool: Synthesis, characterization and catalytic activity

2016 ◽  
Vol 20 (06) ◽  
pp. 677-688 ◽  
Author(s):  
Ahmad Shaabani ◽  
Zeinab Hezarkhani
Keyword(s):  
Catalytic Activity ◽  
Carbonyl Compounds ◽  
Aerobic Oxidation ◽  
Significant Loss ◽  
X Ray Diffraction ◽  
Flame Atomic Absorption Spectroscopy ◽  
X Ray ◽  
Flame Atomic Absorption ◽  
Eds Analysis ◽  
Ft Ir

Functionalized wool with cobalt(II), copper(II), and iron(II) tetrasulfophthalocyanine (CoTSPc@wool, CuTSPc@wool, and FeTSPc@wool) have been synthesized and their structures characterized by flame atomic absorption spectroscopy (FAAS), FT-IR, UV-vis, X-ray diffraction (XRD), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and the energy dispersive spectroscopy (EDS) analysis. The catalytic activity of the synthesized catalysts was investigated for the aerobic oxidation of alkyl arenes and alcohols to their corresponding carbonyl compounds in the absence of any co-promoter and additional oxidizing reagent. We found the best catalyst for the mentioned reactions is the CoTSPc@wool from the solvent, conversion, temperature, and reaction time point of views. The synthesized catalysts can be readily recycled and reused for several runs without significant loss of efficiency.

scholarly journals Oxido- and Dioxido-Vanadium(V) Complexes Supported on Carbon Materials: Reusable Catalysts for the Oxidation of Cyclohexane

Nanomaterials ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1456
Author(s):  
Manas Sutradhar ◽  
Marta A. Andrade ◽  
Sónia A. C. Carabineiro ◽  
Luísa M. D. R. S. Martins ◽  
Maria de Fátima C. Guedes da Silva ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Carbon Materials ◽  
Ionization Mass ◽  
X Ray Diffraction ◽  
Functionalized Carbon Nanotubes ◽  
X Ray ◽  
Tert Butylhydroperoxide ◽  
Ft Ir ◽  
First Time ◽  
Catalytic Performances

Oxidovanadium(V) and dioxidovanadium(V) compounds, [VO(OEt)L] (1) and [Et3NH][VO2L] (2), were synthesized using an aroylhydrazone Schiff base (5-bromo-2-hydroxybenzylidene)-2-hydroxybenzohydrazide (H2L). They were characterized by elemental analysis, Fourier-transform infrared spectroscopy (FT-IR), (1H and 51V) nuclear magnetic resonance (NMR), electrospray ionization mass spectrometry (ESI-MS) and single crystal X-ray diffraction analyses. Both complexes were immobilized on functionalized carbon nanotubes and activated carbon. The catalytic performances of 1 and 2, homogenous and anchored on the supports, were evaluated for the first time towards the MW-assisted peroxidative oxidation (with tert-butylhydroperoxide, TBHP) of cyclohexane under heterogeneous conditions. The immobilization of 1 and 2 on functionalized carbon materials improved the efficiency of catalytic oxidation and allowed the catalyst recyclability with a well-preserved catalytic activity.

Low-temperature Raman and Fourier transform infrared spectra of dodecacarbonyldirhenium(0), Re2(CO)10

1985 ◽  
Vol 63 (7) ◽  
pp. 1510-1517 ◽  
Author(s):  
Pierre D. Harvey ◽  
Ian S. Butler
Keyword(s):  
Fourier Transform ◽  
Low Temperature ◽  
Room Temperature ◽  
Metal Carbonyl ◽  
Carbonyl Complex ◽  
X Ray ◽  
Temperature Spectra ◽  
Ft Ir ◽  
Ir Study ◽  
First Time

The Raman spectrum of microcrystalline dodecacarbonyldirhenium(0), Re2(CO)10, has been reinvestigated at 67 K using one of the latest fully-computerized spectrometers available. Previously unobserved peaks have been detected mainly in the 13CO-satellite (2150–1900 cm−1), and overtone and combination regions (1300–700 and 4300–3800 cm−1). This is the first time that Raman-active first CO overtones and combinations of a metal carbonyl complex have been reported. They were earlier thought to be too weak to be detected. Assignments are proposed for the majority of these new peaks together with those from a similar low-temperature (~70 K) FT-ir study. In general, the D4d selection rules are obeyed, but the activity of some forbidden bands reveals that the molecule is slightly distorted in the solid state in agreement with its X-ray structure. The similarity of the low-temperature spectra to those obtained at room temperature indicates that no phase change occurs throughout the temperature range investigated.

scholarly journals New Insights on the Stradivari “Coristo” Mandolin: A Combined Non-Invasive Spectroscopic Approach

2021 ◽  
Vol 11 (24) ◽  
pp. 11626
Author(s):  
Francesca Volpi ◽  
Giacomo Fiocco ◽  
Tommaso Rovetta ◽  
Claudia Invernizzi ◽  
Michela Albano ◽  
...  
Keyword(s):  
Ir Spectroscopy ◽  
String Instruments ◽  
X Ray ◽  
Non Invasive ◽  
Ft Ir ◽  
Iron Based ◽  
Materials Used ◽  
First Time ◽  
Violin Making ◽  
Ft Ir Spectroscopy

In this work, one of the two existing mandolins made by Antonio Stradivari has been investigated for the first time, as a rare exemplar of the lesser-known class of plucked string instruments. The mandolin was studied by non-invasive reflection Fourier transformed infrared (FT-IR) spectroscopy and X-ray fluorescence (XRF) on different areas previously selected by UV-induced fluorescence imaging. The analytical campaign was aimed at (i) identifying the materials used by Stradivari in the finishing of the mandolin, (ii) comparing these materials with those traditionally used in violin making, and (iii) increasing the knowledge of materials and techniques applied by Stradivari in the rare production of plucked string instruments. The combined spectroscopic approach allowed us to hypothesize original materials and finishing procedures similar to those used in violin making: a possible sizing treatment of the wood with protein-based materials and silicates, externally coated with an oil–resin varnish. XRF results were essential to support FT-IR findings and to detect possible iron-based pigments in the finishing layers. Moreover, it permitted us to distinguish original areas from the restored areas, including the purflings on the top plate and the varnished area on the treble side of the mandolin for which the originality was assumed.

Surface Characterization of Chinese Fir/TiO2 Composite

2011 ◽  
Vol 189-193 ◽  
pp. 653-657
Author(s):  
Su Yong Huang ◽  
Kai Fu Li
Keyword(s):  
Photoelectron Spectroscopy ◽  
Surface Characterization ◽  
Sol Gel ◽  
Chinese Fir ◽  
Small Samples ◽  
Liquid Phase Deposition ◽  
X Ray ◽  
Ft Ir ◽  
First Time

Small samples of Chinese fir/TiO2 composites were prepared by sol-gel method and MWLPD (microwave assistant liquid phase deposition) method for the first time. The surface of samples were analyzed by Fourier transform infrared (FT-IR) and X-ray photoelectron spectroscopy (XPS), and the microstructure and Ti distribution of samples was observed by scanning electron microscopy and energy dispersive spectroscopy (SEM-EDS). Results show that Ti is not only distributed on the composites surface, but also go into the inside wood. The composites surfaces are covered with pure TiO2. Activities of composites are increased considerably for the oxygen content and number of oxygen containing groups on there surfaces are increased considerably.

Computer programs for the calculation of x-ray intensities emitted by elements in multi-layer structures

1990 ◽  
Vol 48 (2) ◽  
pp. 216-217
Author(s):  
G.F. Bastin ◽  
H.J.M. Heijligers ◽  
J.M. Dijkstra
Keyword(s):  
Software Package ◽  
Light Element ◽  
Matrix Correction ◽  
Excellent Performance ◽  
Element Analysis ◽  
X Ray ◽  
Know How ◽  
Accurate Knowledge ◽  
Layer Structures ◽  
Bulk Matrix

For the calculation of X-ray intensities emitted by elements present in multi-layer systems it is vital to have an accurate knowledge of the x-ray ionization vs. mass-depth (ϕ(ρz)) curves as a function of accelerating voltage and atomic number of films and substrate. Once this knowledge is available the way is open to the analysis of thin films in which both the thicknesses as well as the compositions can usually be determined simultaneously.Our bulk matrix correction “PROZA” with its proven excellent performance for a wide variety of applications (e.g., ultra-light element analysis, extremes in accelerating voltage) has been used as the basis for the development of the software package discussed here. The PROZA program is based on our own modifications of the surface-centred Gaussian ϕ(ρz) model, originally introduced by Packwood and Brown. For its extension towards thin film applications it is required to know how the 4 Gaussian parameters α, β, γ and ϕ(o) for each element in each of the films are affected by the film thickness and the presence of other layers and the substrate.

Synthesis and Evaluation of Levulinic Ester as Biodiesel Additives

2020 ◽  
Vol 71 (8) ◽  
pp. 21-26
Author(s):  
Elena-Emilia Oprescu ◽  
Cristina-Emanuela Enascuta ◽  
Elena Radu ◽  
Vasile Lavric
Keyword(s):  
Maximum Yield ◽  
Strength Distribution ◽  
Point Of View ◽  
Reaction Parameters ◽  
X Ray ◽  
Ethyl Levulinate ◽  
Ft Ir ◽  
Ir Analysis ◽  
Biodiesel Blend ◽  
Acid Strength Distribution

In this study, the SO42-/TiO2-La2O3-Fe2O3 catalyst was prepared and tested in the conversion of fructose to ethyl levulinate . The catalyst was characterized from the point of view of the textural analysis, FT-IR analysis, acid strength distribution, X-ray powder diffraction and pyridine adsorption IR spectra. The influence of the reaction parameters on the ethyl levulinate yield was study. The maximum yield of 37.95% in levulinate esters was obtained at 180 �C, 2 g catalyst and 4 h reaction time. The effect of ethyl levulinate addition to diesel-biodiesel blend in different rates, i.e, 0.5, 1, 2.5, 5 (w.t %) on density, kinematic viscosity and flash point was evaluated and compared with the European specification.

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