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1
Content available Spectroscopic Studies of Mixed-ligand Complexes of Chelating Agents Containing O, N and S Donor Atom and Divalent Metal Ions
100%
Ishola K. T. , Odedokun O. A. , Bolarinwa O. T. , Ajayi T. A. , Adeyemi M. I.
World Scientific News
|
2023
|
tom 180
70-81
EN
The study of coordination chemistry of mixed-ligand complexes especially metal complexes of chelating agents with functional groups specifically identical with those present in enzymes has provided useful information about their binding tendency which could be exploited in various analytical and biological reactions. This research investigated spectroscopic properties of mixed-ligand complexes of Co(II) and Mn(II) with tyrosine, methionine and thiobarbituric acid using elemental analysis, metal analysis, solubility test, infrared and UV-Visible spectroscopy. The results of elemental and metal analysis ascertained the molecular masses of the complexes and the formation of 1:1:1 metal to ligands ratio. The complexes were insoluble in the tested solvent except dimethylsuphoxide where they are soluble. IR spectral suggested coordination of the ligands to the metal ions through nitrogen and oxygen donor atoms. UV-Visible analysis revealed tentative octahedral geometry for the complexes. It is concluded that the information provided in this study could be useful in characterizing newly synthesized chelating agents.
2
Content available Synthesis and characterization of copper (II) mixed ligand complexes with 3-proply-5-mercapto-1,2,4-triazole and 1,10-phenanthroline
100%
Obeten A. U. , Eno E. A. , Offiong O. E. , Akakuru O. U.
World Scientific News
|
2022
|
tom 166
43-53
EN
New horizon for scientific research in coordination compounds has gained interest for decades, aided by the field of bioinorganic chemistry that encompasses investigating the role of metal complexes in biochemical systems. Consequently, various coordination compounds have been successfully synthesized and extensively evaluated for application in many aspects of science, pharmacy and medicine. Here, copper (II) mixed ligands complex was synthesized using 3-propyl-5-marcapto-1,2,4-triazole and 1,10-phenanthroline. The complex was characterized by melting points, solubility and molar conductivity in various solvent to establish its properties that could guide its subsequent practical applications. Drawing from the limited experimental data and existing literature on very similar works a tentative octahedral geometry has been proposed for the Cu (II) Complex. It is therefore expected that this study will guide the development of other coordination compounds with wide-range application prospects.
3
Content available Synthesis of a novel environmental friendly plasticizer based on tung oil fatty acid for poly (vinyl chloride) blends
100%
Tong H. , Hai J.
Polish Journal of Chemical Technology
|
2018
|
tom Vol. 20, nr 2
92--97
EN
A novel environmental friendly plasticizer (TPE) derived from tung oil fatty acid with long fatty acid chain and high degree of branching was synthesized. Chemical structure of the obtained TPE was characterized with Fourier transform infrared spectroscopy (FT-IR) and  1H NMR. TPE was used to prepare plasticized PVC blends as main plasticizer. Thermal stability, mechanical properties and migration resistance of poly (vinyl chloride) plasticized with TPE were investigated. The results showed that torque data of plasticized PVC blends reached 12.4 N·m when the mass of the TPE was 50 wt.%. TPE improved the thermal stability of PVC blends obviously than dioctyl phthalate (DOP). The leaching tests showed that PVC plasticized with TPE were with higher migration resistance than that of DOP. The excellent thermal stability and high migration resistance of PVC blends showed high application value for TPE.
4
Content available Synthesis and LFER study of some substituted hydrazones
100%
Vijayakumar R. , Rajarajan M. , Senbagam R. , Balaji S. , Manikandan V. , Vanangamudi G. , Thirunarayanan G.
World Scientific News
|
2017
|
tom 66
263-280
EN
A series containing ten substituted hydrazones have been synthesized by condensation between semicarbazide and various substituted benzaldehydes. The hydrazones were confirmed by their physical constants and UV, IR, 1H NMR and 13C NMR spectral data. This UV, IR, 1H NMR and 13C NMR spectral data have been used for LFER studied with Hammett constants and Swain-Lupton’s parameters.
5
Content available remote Synthesis and characterization of thermoresponsive hydrogels cross-linked with chitosan
100%
Yu Y. , Chang X. , Ning H. , Zhang S.
Open Chemistry
|
2008
|
tom 6
|
nr 1
107-113
EN
Hydrogels composed of N-isopropylacrylamide (NIPAAm) and acrylic acid (AAc) were prepared by redox polymerization with degradable chitosan cross-linkers. Chitosan degradable cross-linkers were synthesized by the acrylation of the amine groups of glucosamine units within chitosan and characterized with 1H NMR. With the chitosan cross-linkers, loosely cross-linked poly(N-isopropylacryamideco-acrylic acid) [P(NIPAAm-co-AAc)] hydrogels were prepared, and their phase transition behavior, lower critical solution temperature (LCST), water content and degradation properties were investigated. The chitosan cross-linked P(NIPAAm-co-AAc) hydrogels were pliable and transparent at room temperature. The LCST could be adjusted at 32∼39°C by alternating the feed ratio. Swelling was influenced by NIPAAm/AAc monomer ratio, cross-linking density, swelling media, and temperature. All hydrogels with different feeding ratios contained more than 95% water at 25°C in the ultra pure water and phosphate-buffered saline (PBS, pH = 7.4 ± 0.1), and had a prospective swelling in the simulated gastric fluids (SGF, pH = 1.2) > 72.54%. In degradation studies, breakdown of the chitosan cross-linked P(NIPAAm-co-AAc) hydrogels was dependent on the cross-linking density. The chitosan cross-linked P(NIPAAm-co-AAc) hydrogels which can be tailored to create environmentally-responsive artificial extracellular materials have great potential for future use. [...]
6
Content available remote Novel organic material with potential NLO application - electronic and spectroscopic properties
100%
Koleva B. B. , Kolev T. , Nikolova R. , Zagraniarsky Y. , Spiteller M.
Open Chemistry
|
2008
|
tom 6
|
nr 4
592-599
EN
Novel dicyanoisophorone derivative, (E)-2-(3-(4-aminostyryl)-5,5-dimethylcyclohex-2-enylidene)malononitrile, is synthesized and its structure elucidated by means of conventional and linear polarized IR-spectroscopy of oriented colloids in nematic host, 1H, 13C, 1H, 1H-COSY NMR, HPLC tandem ESI MS-MS spectrometry, UV-VIS and thermal methods. Ab initio and DFT level of theory are used to theoretically obtain the electronic structure and optical properties, both in ground and exited state, of the compound. [...]
7
Content available remote Synthesis of hydroxyapatite by using calcium carbonate and phosphoric acid in various water-ethanol solvent systems
100%
Engin A. , Girgin İ.
Open Chemistry
|
2009
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tom 7
|
nr 4
745-751
EN
The purpose of the present study is to synthesize hydroxyapatite by using CaCO3 and H3PO4 in various water-ethanol solvent systems. It was observed from experiments that formation of ammonium phosphate compounds hindered the formation of calcium phosphates in ethanol medium. Although the reactivity was better in aqueous medium, the carbonate contents of the products obtained were above 8.5%. Best results with a carbonate content as low as 3.82% was obtained in 50% ethanol containing mixed-aqueous medium at 80°C and the FTIR analysis showed that the product was a carbonated apatite with a calculated composition of 14CaO·4.2P2O5·CO3·7.2H2O. The amorphous and porous phosphate compound obtained with a BET surface area of 106.6 m2 g−1 seems to be useful as adsorbent in wastewater treatment. Upon sintering of the amorphous product at 750°C, crystalline hydroxyapatite with a BET surface area of 25.9 m2 g−1 is obtained that may be used in biomedical applications. [...]
8
Content available remote A review on the synthesis of TiO2 nanoparticles by solution route
100%
Gupta S. , Tripathi M.
Open Chemistry
|
2012
|
tom 10
|
nr 2
279-294
EN
TiO2 can be prepared in the form of powder, crystals, or thin films. Liquid-phase processing is one of the most convenient and utilized methods of synthesis. It has the advantage of allowing control over the stoichiometry, production of homogeneous materials, formation of complex shapes, and preparation of composite materials. However, there may be some disadvantages such as expensive precursors, long processing times, and the presence of carbon as an impurity. In comparison, the physical production techniques, although environment friendly, are limited by the size of the produced samples which is not sufficient for a large-scale production. The most commonly used solution routes in the synthesis of TiO2 are reviewed.
9
Content available Spectral studies and antimicrobial activities of some (E)-N-(substituted benzylidene)-2,6-diisopropylanilines
88%
Thirunarayanan G. , Manikandan V. , Aarulkumaran R. , Rarajan R. , Usha V.
World Scientific News
|
2017
|
tom 66
20-42
EN
A series of Schiff’s base compounds were synthesized from 2,6-di(propan-2-yl) aniline with substituted aromatic aldehydes. The structures of all the synthesized compounds were characterized by physical constants, IR and NMR spectroscopic techniques. All the observed IR frequencies νC=N (cm-1), NMR δ(ppm) of C-H & C=N chemical shifts have been correlated with Hammett substituent constants and F and R parameters using single and multi-linear regression analyses in order to study the effect of substituents on these spectral data has been studied. All the synthesized Schiff’s base compounds were screened for their antimicrobial activity by disc diffusion method.
10
Content available remote Synthesis and monolayer film of a series of new twin-tailed gemini cationic surfactants at the air/water interface
88%
Chen Z. , Feng Y. , Zhou D. , Zhu P. , Wu D.
Open Chemistry
|
2008
|
tom 6
|
nr 3
477-481
EN
A series of new dimeric surfactants, twin-tailed gemini surfactants, 2(12)-s-2(12), were successfully prepared and characterized, and their monolayer films investigated by the measurement of surface pressure-area (π-A) and surface pressure-time (π-t) isotherms at the air/water interface by a Langmuir film balance. Compared to their monomeric counterparts, their collapse pressure (γcollapse) is smaller, whilst all the molecular area parameters are larger. The limited area (Alimited) and the initial area (Ainitial) of these twin-tailed gemini surfactants change with increasing spacer length s, and the surface pressure decreases with increasing time. It was also found that the higher the initial surface pressure, the larger the attenuation. [...]
11
Content available remote Development of FeOOH nanoarrays using magnetic cations
88%
Garcia-Casillas P. , Martinez-Pérez C. , González C. , Camacho-Montes H. , Martel Estrada S. , Armendáriz I.
Open Chemistry
|
2013
|
tom 11
|
nr 3
358-363
EN
Abstract In this work, FeOOH arrays were obtained using two different magnetic cations. The nanoparticles were grouped into a package having different orientations through the van der Waals interaction with the magnetic cations. With Fe2+, the FeOOH nanoparticles have a rod shape with a 30-nm diameter and approximately 1-micron length, and are aligned in a star structure. With Co2+, a somatoidal shape was observed, with 20-nm diameter and 150-nm length and a pathway structure to the array. The chemical synthesis method was used to obtain the nanoarrays. The morphology and the average size of the nanorods and nanowires were determined using Field Emission Scanning Electron Microscopy (FESEM). Fourier Transform Infrared Spectroscopy (FTIR) was used to study the interaction between the nanorods and the cobalt ions. The phases of the material were identified using X-ray Diffraction. Graphical abstract [...]
12
Content available remote Paclitaxel as an anticancer agent: isolation, activity, synthesis and stability
88%
Nikolic V. , Savic I. , Savic I. , Nikolic L. , Stankovic M. , Marinkovic V.
Open Medicine
|
2011
|
tom 6
|
nr 5
527-536
EN
Paclitaxel is isolated from the Pacific yew. It can be obtained from the European yew, but only after chemical modification of the isolated compound by a semi-synthesis procedure. The procedure for total synthesis of paclitaxel is very complicated, involving multiple steps, and the yields of paclitaxel are meagre. This substance is also a metabolite of certain kinds of fungus. The microbiological pathway for producing paclitaxel compared with isolation from plant material involves shorter procuction times but a small yield. Cyclodextrins are usually used for improving the solubility of paclitaxel in aqueous media, with polymeric and other substances added. Paclitaxel has anticancer activity and use for preparing the formulations intravenously administrated to patients with tumors. The paclitaxel concentration in these formulations is determined using validated HPLC methods.
13
Content available In silico screening, synthesis, in vitro evaluations antibacterial and DPPH scavenging activity of some 1,3,5-trisubstituted 2-pyrazoline derivatives as dihydrofolate reductase inhibitors
88%
Suriya S. , Mala V.
World News of Natural Sciences
|
2018
|
tom 18
|
nr 2
180-186
EN
In this work, synthesis of three pyrazoline derivatives (6-8) is described. (E)-1,3-(phenylsubstituted)-prop-2-en-1-one (3-5) is prepared by the reaction of substituted benzaldehyde with 4-methylacetophenone, whereas condensation cyclization of the same chalcones (3-5) with phenylhydrazine hydrate in ethanol yielded 6-8. The structures of the title compounds (6-8) were characterized by chemical reactions, elemental analysis, and spectral methods such as IR spectra. The synthesized chalcone and pyrazolines were evaluated for in-vitro antibacterial and antioxidant activities against standard. The zone of inhibition for some of the newly synthesized compounds showed notable antibacterial activity against selected bacterial strains when compared with ampicillin. Significant antioxidant activities were also shown by chalcone and pyrazolines.
14
Content available remote Synthesis and structural characterization of amino-functionalized polysaccharides
88%
Sisu I. , Udrescu V. , Flangea C. , Tudor S. , Dinca N. , Rusnac L. , Zamfir A. , Sisu E.
Open Chemistry
|
2009
|
tom 7
|
nr 1
66-73
EN
A variety of carbohydrates, in particular polysaccharides can be subjected to chemical modification to obtain derivatives with amphiphilic properties, which enable biochemical or biological reactions at the polymer surface. In the present work, a polydisperse maltodextrin mixture of average molecular weight 3000 was coupled with 1,6-hexamethylenediamine (HMD) via reductive amination reaction. Resulting products were characterized by thermal analysis and positive nanoelectrospray quadrupole time-of-flight (Q-TOF) mass spectrometry (MS) and tandem mass spectrometry (MS/MS). Both thermal analysis and MS screening confirmed the formation of the HMD-polysaccharide coupling products. Moreover, HMD-linked polysaccharide chains containing 2 to 26 glucose building blocks were identified by nanoESI Q-TOF MS. MS/MS fragmentation using collision-induced dissociation (CID) at low ion acceleration energies provided strong evidence for HMD-maltodextrin linkage formation and the set of sequence ions diagnostic for the composition and structure of a HMD-linked chain containing 18 glucose residues. [...]
15
Content available Gamma-Irradiations Effects on Structural and Micro-Structural Parameters of Chromium(III) – Silicate Base Mica Clay
75%
Elsabawy K. M. , Abou-Sekkinaa M. M.
World Scientific News
|
2016
|
tom 32
13-23
EN
Solution route was applied to synthesize new family of free-fluoride synthetic clay. All starting solutions were made by applying carbon tetra-chloride (CCl4) as a solvent. The selected sample of synthetic free fluoride – Na-4-mica was having the general formula (Na4Mg6M4Si4O22•nH2O) where M = Cr3+ was exposured to two different ɤ-irradiation doses 1st dose = 1.5 MR/h and 2nd dose = 3 MR/h at 25 cm distance. Structural parameters such as lattice constants, volume and phase quality were monitoring carefully by using both of XRD and SEM evaluating grain size of the mica bulk. Structural investigations proved that Cr-clay exhibits monoclinic phase accompanied with structure quality in comparison with both of Bi-and Al-clays
16
Content available Nano-Structural Features, Raman Spectra and New Trend of 3D-AFM Investigations for High Performance Ni-Super-alloy
75%
Elsabawy K. M. , Elbagoury N. H.
World Scientific News
|
2016
|
tom 34
34-50
EN
The synthesized Ni-alloy was prepared via conventional casting technique under vacuum and highly superheated treatment route. The casting parameters such as solidification cooling rate (SCR) was monitoring by both of AFM and SEM .Micro-structural investigations within different spots in the same sample indicated that γ matrix is the domain phase besides minor phases as MC carbides, σ phase and η phase which was observed to solidify in two forms as plate-like and blocky shape. The volume fraction (Vf) of σ and η phases was increased as the solidification cooling rate decreases. 3D-microstructural imaging map of the Ni-based super-alloy was constructed depending upon AFM-data evaluating that the morphology of the alloy-surface is a function of casting parameters .Furthermore raman spectra of highly superheated casted Ni-based super-alloy was performed to confirm existence of different phases recorded via SEM and EDX-elemental analysis with their corresponding different vibrational modes such as Ni-O vibrating modes in the region 360-510 cm-1 and Mo-O vibrating mode which lies at 1005 cm-1.
17
Content available Synthesis and Measurement of Physical and Acoustical Parameters of Poly(Ethyleneglycol-600 Maleate) Resin
75%
Pandya D. , Parsania P. H.
World Scientific News
|
2019
|
tom 117
82-101
EN
Poly(Ethyleneglycol-600 Maleate) Resin was synthesized and characterized by FT-IR. The physical and acoustical parameters such as Intrinsic viscosity, Acid value, Density, Viscocity, Sound velocity, Wavelength, Isentropic compressibility, Specific acoustical impedance, Rao’s molar sound function, Apparent molecular weight, Van-der Waal’s constant, Internal pressure, Classical absorption coefficient, Viscous relaxation time, Solvation number, Apparent molar volume, Apparent molar compressibility, Free volume and Inter molecular free path length were determined.
18
Content available Synthesis, spectral studies and antimicrobial activities of some substituted (E)-1-benzylidene-2-(4-bromophenyl)hydrazines
75%
Rajarajan M. , Senbagam R. , Vijayakumar R. , Manikandan V. , Balaji S. , Vanangamudi G. , Thirunarayanan G.
World Scientific News
|
2015
|
tom 9
144-160
EN
A series of nine number of (E)-1-benzylidene-2-(4-bromophenyl)hydrazine compounds have been synthesized by the condensation reaction of 4-bromo phenylhydrazine with varies m- and p- substituted benzaldehydes using acetic acid catalyst were refluxed for 4h with 20 mL of absolute ethanol. The yield of synthesized (E)-1-benzylidene-2-(4-bromophenyl)hydrazine compounds are more than 80%. The synthesized (E)-1-benzylidene-2-(4-bromophenyl)hydrazines have been characterized by UV, IR, 1H and 13C spectral data. These UV, IR and NMR spectral data have been correlated with varies Hammett substituted constant and Swain-Lupton F and R parameters using single and multi- regression analysis. From the results of statistical analysis, the effects of substituent have been studied. The antimicrobial activity of all the synthesized substituted (E)-1-benzylidene-2-(4-bromophenyl)hydrazines have been evaluated using Bayer-Kirby method.
19
Content available Synthesis and Measurement of Physical and Acoustical Parameters of Poly(Ethyleneglycol-400 Maleate) Resin
75%
Pandya D. , Parsania P. H.
World Scientific News
|
2019
|
tom 118
144-163
EN
Poly(Ethyleneglycol-400 Maleate) Resin was synthesized and characterized by FT-IR. The physical and acoustical parameters such as Intrinsic viscosity, Acid value, Density, Viscocity, Sound velocity, Wavelength, Isentropic compressibility, Specific acoustical impedance, Rao’s molar sound function, Apparent molecular weight, Van-der Waal’s constant, Internal pressure, Classical absorption coefficient, Viscous relaxation time, Solvation number, Apparent molar volume, Apparent molar compressibility, Free volume and Inter molecular free path length were determined.
20
Content available Effects of PVA Polymer Type and Calcination Temperature on Synthesis of Nanocrystalline Yttria Powder by Polymer Solution Route
63%
Yang Y.-K. , Lee S.-J.
|
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