The reaction of L (MAD) with Cu2+ and Co2+ chlorides affords new metal complexes. The isolated solid complexes were synthesized by two different techniques i.e., chemical and tribochemical methods. Four new complexes ...The reaction of L (MAD) with Cu2+ and Co2+ chlorides affords new metal complexes. The isolated solid complexes were synthesized by two different techniques i.e., chemical and tribochemical methods. Four new complexes were synthesized by direct chemical reactions of MCl2 (M = Co2+ and Cu2+) with MAD in absolute EtOH. The isolated solid complexes were used as starting compounds to synthesize another four new complexes using tribochemical technique by grinding the previous complexes in the solid state with excess KI in agate mortar. The results of the isolated complexes indicate the substitution of the chloride by iodide ions during grinding and extraction of the complexes by a mixture of solvents (EtOH + MeOH). Also, the results suggest that no reduction of Cu2+ or oxidation of Co2+ complexes is observed. The IR spectra of the complexes suggest that L acts in a bidentate manner. Moreover, the results of electronic spectra and magnetic measurements for the chloride and iodide complexes suggest distorted-octahedral and/or tetrahedral for Cu2+ and high-spin octahedral and/or tetrahedral structures around the Co2+ ion, respectively.展开更多
The reaction of benzene-1,2,3-tricarboxylate copper(II) trihydrate (Cu<sub>3</sub>(1,2,3-BTC)<sub>2</sub>·3H<sub>2</sub>O) and ethylenediamine (en) gave after recrystallization...The reaction of benzene-1,2,3-tricarboxylate copper(II) trihydrate (Cu<sub>3</sub>(1,2,3-BTC)<sub>2</sub>·3H<sub>2</sub>O) and ethylenediamine (en) gave after recrystallization from methanol at room temperature violet crystalline solid of the polymeric two dimensional material {[Cu<sub>3</sub>(<em>μ</em><sub>3</sub>-1,2,3-BTC)(<em>μ</em><sub>2</sub>-1,2,3-BTC)(en)<sub>3</sub>(OH<sub>2</sub>)<sub>2</sub>(OH)(<em>μ</em><sub>2</sub>-OH<sub>2</sub>)]<sub>2</sub>·5H<sub>2</sub>O·O}<sub>n</sub> (1) as identified by single crystal X-ray diffraction analysis. The compound was also characterized by elemental analysis, FT-IR spectroscopy, UV-vis spectroscopy, thermogravimetric analysis (TGA) and magnetic susceptibility. The molecular structure indicates crystallization in the triclinic space group P-1 with the unit cell parameters a = 12.1205(3) <span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;">Å</span></span></span></span>, b = 12.7026(3) <span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;">Å</span></span></span></span>, c = 13.9890(3) <span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;">Å</span></span></span></span>, <em>α</em> = 75.034(1)<span style="white-space:nowrap;">°</span>, <em>β</em> = 74.957(1)<span style="white-space:nowrap;">°</span>, <em>γ</em> = 68.415(1)<span style="white-space:nowrap;">°</span>. Structural analysis also revealed that the dimeric compound is connected by Cu-O-Cu bridges and the dimer is further converted into a polymeric chain structure through bridging of one benzene-1,2,3-tricarboxylate ligand. Different coordination modes are observed at the copper atom. The Cu atom at the center is octahedral while the two other ones are pentacoordinated. Thermal analysis of the compound showed decomposition processes, while magnetic studies indicated a magnetic susceptibility <em>μ</em> of 3.21 BM.展开更多
The kinetics of the periodate oxidation of chromium(III)-complex, [CrIII(NTA)(Ala)(H2O)]-(NTA = Nitrilotriacetate and Ala = ß-alanine) to Cr(VI) have been carried out for the temperature range 15°C - 35&...The kinetics of the periodate oxidation of chromium(III)-complex, [CrIII(NTA)(Ala)(H2O)]-(NTA = Nitrilotriacetate and Ala = ß-alanine) to Cr(VI) have been carried out for the temperature range 15°C - 35°C under pseudo-first order conditions, >>?[complex]. Reaction obeyed first order dependence with respect to and [Cr(III)], and the rate of reaction increases with increasing of pH for the range 3.40 - 4.45. Experimentally, the mechanism of this reaction is found to be consistent with the rate law in which the hydroxo species, [CrIII(NTA)(Ala)(OH)]2- is considerably much more reactive than their conjugate acid. ΔH* and ΔS* have been calculated. It is proposed that electron transfer occurs through an inner-sphere mechanism via coordination of to chromium(III).展开更多
Two novel copper complexes (<strong>1,2</strong>) with N,O-donor ligands were synthesized by reaction of copper(II) malonates with 3,3’-bis(pyrazolyl)pentane and 4,4’-trimethylenedipyridine in methanol a...Two novel copper complexes (<strong>1,2</strong>) with N,O-donor ligands were synthesized by reaction of copper(II) malonates with 3,3’-bis(pyrazolyl)pentane and 4,4’-trimethylenedipyridine in methanol at moderate temperature. These compounds were characterized by elemental analysis, UV-VIS, IR spectroscopies and powder X-ray diffraction analyses. Compound (<strong>1</strong>) melts at higher temperature (202°C) than compound (<strong>2</strong>) (100<span style="white-space:normal;">°</span>C). The IR spectra showed typical vibrations related to C=N and C=C, characteristic of pyrazolyl and pyridine ligands.展开更多
Phenylalanine, isocoumarin and Ochratoxin A (OTA) have been intercalated within the interlayer space of layered double hydroxides. Synthesis of these nanocompounds was achieved via co-precipitation. Their physicochemi...Phenylalanine, isocoumarin and Ochratoxin A (OTA) have been intercalated within the interlayer space of layered double hydroxides. Synthesis of these nanocompounds was achieved via co-precipitation. Their physicochemical properties were studied by element chemical analysis, powder X-ray diffraction, infrared spectroscopy and thermal analyses. The presence of OTA in the interlayer is demonstrated by the study of LC-FD Analysis. On the other hand, these studies allow to check how some of the toxin is on the surface of the nanocomposite.展开更多
The aim of this work was to test the adsorption efficiency of copper (II) ions in an aqueous solution on Natural Smectite (NS) and Activated Carbon (AC). The experiments carried out in batch mode made it possible to d...The aim of this work was to test the adsorption efficiency of copper (II) ions in an aqueous solution on Natural Smectite (NS) and Activated Carbon (AC). The experiments carried out in batch mode made it possible to determine the stirring time, the adsorbent mass, the pH, the initial concentration of copper (II) ions, the isotherms and the adsorption kinetics. It appears that the stirring time was 15 minutes for the AC and 20 minutes for the NS. The adsorption was at maximum for the two adsorbents at optimum pH of 3.5 for a mass of 0.05 g each. The quantity of copper (II) ions adsorbed was 26.6 mg/L for NS and 36.6 mg/g for AC of a concentration of 600 mg/L each. The Langmuir isotherm was the one that best described the adsorption process for the two adsorbents. The adsorption kinetics obtained was that of the pseudo second-order for our two adsorbents. The results obtained showed that these two adsorbents were effective for the adsorption of copper (II) ions in an aqueous solution.展开更多
Schiff base derived from 2-aminophenol and 3-formyl-2-hydroxy-6-methoxyquinoline and its Mn(II) and Fe(II) complexes were synthesized and characterized by melting point and decomposition temperature, elemental analysi...Schiff base derived from 2-aminophenol and 3-formyl-2-hydroxy-6-methoxyquinoline and its Mn(II) and Fe(II) complexes were synthesized and characterized by melting point and decomposition temperature, elemental analysis, molar conductivity, infrared (IR) spectral analysis, atomic absorption spectroscopy (AAS) analysis, solubility test, and magnetic susceptibility. The Fourier-transform infrared spectroscopy (FTIR) spectral data of the Schiff base determined showed <span><span style="font-family:Verdana;">a band at 1622 cm</span><sup><span style="font-family:Verdana;"><span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;">−</span></span></span>1</span></sup><span style="font-family:Verdana;"> and this was assigned to the </span><i><span style="font-family:Verdana;">v </span></i><span style="font-family:Verdana;">(C=N), which is a feature of azomethine group. The same band was observed to shift to lower frequencies 1577 and 1599 cm</span><sup><span style="font-family:Verdana;"><span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;">−</span></span></span>1</span></sup><span style="font-family:Verdana;"> in the complexes suggesting coordination of the Schiff base with the respective metal(II) ions. Molar conductan</span></span><span><span style="font-family:Verdana;">ce values 14.58 and 12.65 Ω</span><sup><span style="font-family:Verdana;"><span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;">−</span></span></span>1</span></sup><span style="font-family:Verdana;"><span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;">∙</span></span></span>cm</span><sup><span style="font-family:Verdana;">2</span></sup><span style="font-family:Verdana;"><span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;">∙</span></span></span>mol</span><sup><span style="font-family:Verdana;"><span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;">−</span></span></span>1</span></sup><span style="font-family:Verdana;"> show that the metal complexes were non-electrolyte in nature. The magnetic susceptibility of the complexes was determined and the gram magnetic susceptibility of the complexes was found to be positive, revealing that they are paramagnetic. The elemental analysis of the complexes for C, N and H determined suggested 1:1 metal to ligand ratio. The result of the antimicrobial studies showed that, the metal(II) complexes exhibited better antibacterial and antifungal activity than the Schiff base.</span></span>展开更多
Seven transition metal complexes of Mn<sup>2+</sup>, Ni<sup>2+</sup>, Co<sup>2+</sup>, Cu<sup>2+</sup> and Zn<sup>2+</sup> with 3-aminopyridine (3-APy) as li...Seven transition metal complexes of Mn<sup>2+</sup>, Ni<sup>2+</sup>, Co<sup>2+</sup>, Cu<sup>2+</sup> and Zn<sup>2+</sup> with 3-aminopyridine (3-APy) as ligand have been synthesized, characterized by different techniques and their antibacterial activities were studied. Molecular modeling calculations were performed using DMOL<sup>3</sup> program in materials studio package which is designed for the realization of large scale density functional theory calculation (DFT). The quantum mechanical and chemical reactivity parameters such as chemical hardness, chemical potential, electronegativity, electrophilicity index and Homo-Lumo energy gap were obtained theoretically and were used to understand the biological activity of the prepared compounds. Some complexes were tested for their in-vitro cytotoxic activity in human lung cancer cell lines (A-549 cell line), and structureactivity relationships were established. In general, the coordination to Co<sup>2+</sup> increased the cytotoxicity while the Ni<sup>2+</sup> complexes show reduced cytotoxic activity compared to the metal-free 3-aminopyridine.展开更多
The coordination behavior of 2,3-butanedionemonoxime Girard’s T hydrazone (L<sup>1</sup>) towards Hg<sup>2+</sup> ion has been investigated. The structure of Hg<sup>2+</sup> comple...The coordination behavior of 2,3-butanedionemonoxime Girard’s T hydrazone (L<sup>1</sup>) towards Hg<sup>2+</sup> ion has been investigated. The structure of Hg<sup>2+</sup> complex, [Hg(L<sup>1</sup>)Cl]Cl·5H<sub>2</sub>O, is elucidated using elemental analyses, spectral (IR, UV-visible, 1H-NMR and mass) and TGA measurements. IR spectrum suggests that L<sup>1</sup> behaves in a bidentate manner through the azomethine groups. The molecular modeling of L<sup>1</sup> and its Hg<sup>2+</sup> complex has been investigated. The bond lengths, bond angles, HOMO and LUMO have been calculated. The thermal behavior and kinetic parameters are determined using Coats-Redfern method. The use of L<sup>1</sup> for preconcentration and separation via flotation of Hg<sup>2+</sup> complex and determination using cold vapor atomic spectrometry (CVAAS) is described. The effects on the percentage of recovered Hg<sup>2+</sup> by pH of sample solutions, oleic acid (HOL) concentration, Hg<sup>2+</sup> and L<sup>1</sup> concentrations are studied in details. The method is applied for the determination of the total Hg<sup>2+</sup> (mg·mL<sup>-1</sup>) in natural water samples.展开更多
Mesoporous molecular sieves, NbFAPO-5 and NbFAPSO-5 were hydrothermally synthesized with AlPO-5 type structure. Characterization of these molecular sieves was performed by X-ray diffraction to determine their structur...Mesoporous molecular sieves, NbFAPO-5 and NbFAPSO-5 were hydrothermally synthesized with AlPO-5 type structure. Characterization of these molecular sieves was performed by X-ray diffraction to determine their structure, ICP-EAS for their elemental composition and infrared spectrometry to access their acidic properties. X-ray diffraction patterns confirmed well AlPO-5 type structure. ICP-EAS analysis confirmed the incorporation of silicon (12.9%), aluminium (15.4%), phosphorous (21.9%), iron (5.62%) and niobium (0.39%) into AlPO-5 framework. Infrared spectrometry analysis showed that both Bronsted and Lewis sites were found in the synthesized samples. The presence of both Bronsted and Lewis acid site led to bifunctional function of NbFAPO-5 and NbFAPSO-5 molecular sieve in promoting both oxidation and esterification reactions. NbFAPSO-5 Bronsted acidity was higher than that of NbFAPO-5 and for Lewis acidity, NbFAPO-5 was higher than that of NbFAPO-5.展开更多
The research on sensitizer for dye sensitized solar cells based on (metallo)porphyrin/phthalocyanine materials were reviewed, and experimental design and assembly method were advised. Latest progress and research stat...The research on sensitizer for dye sensitized solar cells based on (metallo)porphyrin/phthalocyanine materials were reviewed, and experimental design and assembly method were advised. Latest progress and research status of sensitizer dyes based on metalloporphyrins applied in dye sensitized solar cells was summarized. The preparation and construction of sensitizer electrodes and dye sensitized solar cells based on metal organic frameworks (MOFs) of (metallo)porphyrin/phthalocyanine were projected.展开更多
Transparent nanostructured BaTiO3 film electrodes were synthesized on conductive substrates from BaTiO3 nanocrystals forming at low temperature. Electrochemical and spectroelectrochemical methods were employed to inve...Transparent nanostructured BaTiO3 film electrodes were synthesized on conductive substrates from BaTiO3 nanocrystals forming at low temperature. Electrochemical and spectroelectrochemical methods were employed to investigate its properties of band energetics and the trap state at different pH values. The flat band edges greatly depended on the pH value of electrolyte, and the flat band edges were -0.70, -0.92 and -1.20 V vs saturated Ag/AgCl at the pH value of 3.0, 6.8 and 13.0, respectively. The results showed that trap state densities also highly depended on pH. The total trap state densities were 3.73 × 1015, 4.02 × 1015 and 6.48 × 1016 cm-2 at pH value of 3.0, 6.8 and 13.0 respectively with maximum located at -0.36 V, -0.50 V and -0.80 V. The results obtained from CVs were in good agreement with that obtained from the measurements of time resolved currents. The size of the peak potentials in the cyclic voltammograms experiments was increased dramatically with the pH value increasing, indicating that traps were surface-related.展开更多
In this paper, the content of water glass before and after adding modifying agent was measured by Trimethylsilyl-gas-chromatography. The experimental results showed that different modulus of water glass could generate...In this paper, the content of water glass before and after adding modifying agent was measured by Trimethylsilyl-gas-chromatography. The experimental results showed that different modulus of water glass could generate different content of mono-silicate acid and oligomeric silicate acid in water glass. After a period of storage, different modulus of water glass led to decrease of silicate content at different levels. Because higher content of Na<sub>2</sub>O in water glass tended to incur the alkaline polymerization, the occurrence of depolymerization of silicate species would lead to an increase of oligomeric silicate species, resulting in a drawback of silicate species content after a period of storage. And contrary to that, lower content of Na<sub>2</sub>O in water glass tended to incur the acidic polymerization. When the modifying agent was added to the newly made water glass, the amount of mono-silicate acid and oligomeric silicate acid also decreased. In modified water glass, the change of each silicate acid species was less than that in unmodified water glass. These results showed that the modifying agent retarded the aging of water glass. It had remarkable significance on the theory and practical application of water glass chemistry.展开更多
n this work, we present synthesis of the compounds trans-[Ru(NH<sub>3</sub>)<sub>4</sub>L(bpa)]<sup>2+</sup> where L is pyridine ligands: pyridine (py), isonicotinamide (isn), 4-ace...n this work, we present synthesis of the compounds trans-[Ru(NH<sub>3</sub>)<sub>4</sub>L(bpa)]<sup>2+</sup> where L is pyridine ligands: pyridine (py), isonicotinamide (isn), 4-acetylpyridine (4-acpy) and 4-picoline (4-pic) and 1,2-bis (4-pyridyl) ethane (bpa), their characterization by UV-visible spectroscopy and electrochemical properties. This series shows intense bands in the region between 400 and 515 nm, allocated bands charge transfer (MLCT), the influence of substituents on the pyridine ring (4-acpy and isn), and the interaction between the ligand and the metal, causing a second MLCT band, which is lighter and has more energy. The compound is characterized by spectroscopy by Fourier transform infrared spectroscopy (FTIR). The displacement observed in the symmetrical stretching of ν<sub>s</sub>(CCN) group in the complex compared with the ν<sub>s</sub>(CCN) group in the free ligand is indicative of coordination of the pyridine group to the Ruthenium (II) metallic center. The electrochemical data (cyclic voltammetry) show that reversibility criteria are well defined and formal E<sub>f</sub> potential, indicating the influence of the pyridine ring substituent.展开更多
The ligand 1-(1-(pyridin-2-yl)ethylidene)carbonohydrazide (H4L1) and 1-(pyridin-2-ylmethylene)carbonohydrazide (H4L2) were prepared by reaction of carbonohydrazide with 2-acetylpyridine or pyridine carbaldehyde respec...The ligand 1-(1-(pyridin-2-yl)ethylidene)carbonohydrazide (H4L1) and 1-(pyridin-2-ylmethylene)carbonohydrazide (H4L2) were prepared by reaction of carbonohydrazide with 2-acetylpyridine or pyridine carbaldehyde respectively in a reflux methanol solution. The complexes are prepared by reaction of the ligand with the appropriate metal salt. These complexes are well characterized by elemental analysis, IR and UV spectroscopies and their structure were determined by single X-ray diffraction technic. In the crystal of the dinuclear complex [Mn2(H4L1)2(H2O)4]·Cl4, 1) each Mn(II) center is seven coordinated by two nitrogen atom and one carbonyl atom of the one ligand and one nitrogen atom and one carbonyl oxygen atom of another ligand molecule. The coordination sphere is completed by two water molecules. Each of the carbonyl oxygen atom acts as bridge between the two Mn(II) centers. In the mononuclear complex [Co(H4L2)(NO3)(H2O)2]·(NO3);2) the Co(II) center is heptacoordinated. The ligand acts in tridentate fashion through two nitrogen atoms and one carbonyl oxygen atom. Two water molecules lie in the apical positions. One nitrate group acts in bidentate manner while the other nitrate group remains uncoordinated. In both complexes the coordination polyhedral are best described as a pentagonal bipyramid. The molecules are linked together in each case by multiple hydrogen bond interaction resulting in a three-dimensional network. The crystallographic data has been deposited in Cambridge Crystallographic Data Centre [CCDC No. 1944387 (complex 1) and 1944386 (complex 2)].展开更多
New transition metal complex of Cobalt(III) of the ligand (E)-3-(1-(2-aminoethylimino)ethyl)-4-hydroxy-2H-chromen-2-one, derived from condensation of ethylene diamine with 3-acetyl-4-hydroxy-chromene-2-one have been s...New transition metal complex of Cobalt(III) of the ligand (E)-3-(1-(2-aminoethylimino)ethyl)-4-hydroxy-2H-chromen-2-one, derived from condensation of ethylene diamine with 3-acetyl-4-hydroxy-chromene-2-one have been synthesized by reaction of cobalt(III) salt and the ligand, in amounts equal to metal-ligand molar ratio of 1:2. Both the Schiff base and the complex of Co(III) were characterized by IR, UV-Vis, 1H NMR- and 13C NMR-spectroscopy techniques. Single crystal X-ray diffraction investigation, at low temperature T = 120 K, shows that the cobalt complex is triclinic P-1, a = 10.426(5) ?, b = 11.3234(2) ?, c = 15.729(5) ?, α(°) = 70.102(4), β(°) = 86.049(4), γ(°) = 82.497(4), Z = 2, and its structure consists of isolated [Co(III)(C13H13N2O3)2]+ complex cations with distorted octahedral geometry, ClO-4 counter anions, acetone solvent and water molecules. The crystal cohesion is stabilized by hydrogen bonds between ligands and water molecules, and ionic interactions between complex cations and counter anions.展开更多
The new salt bis(4,5-dihydro-1H-benzo[g]indazole)silver(I) hexafluorophosphate, [Ag(N2H10C11)2]PF6, has been synthesized in methanol at ambient temperature and characterized by elemental and thermal analyses, FTIR and...The new salt bis(4,5-dihydro-1H-benzo[g]indazole)silver(I) hexafluorophosphate, [Ag(N2H10C11)2]PF6, has been synthesized in methanol at ambient temperature and characterized by elemental and thermal analyses, FTIR and 1HNMR spectroscopies, Rietveld refinement from powder diffraction data and DFT studies. The salt crystallizes in the triclinic space group P-1 with the parameters: a = 7.776 ?, b = 8.676 ?, c = 9.226 ?, α = 69.27° β = 89.86°, γ = 74.50°, V = 558.02 ?3, Z = 1. In the structure, the silver center is coordinated to two nitrogen atoms from two 4,5-dihydro-1H-benzo[g]indazole ligands, forming a centrosymmetric complex cation, [Ag(N2H10C11)2]+, with a linear coordination geometry around the silver center. The hexafluorophosphate ion, , acts as counter anion. The crystal packing is governed by N-H···F and C-H···F hydrogen bonds that interconnect the ionic constituents and Ag···F and Ag···π interactions help for the stabilization of the packing. The optimized structure was obtained at B3LYP/LanL2DZ level in the gas phase. The stability and reactivity of the structure were studied using respectively HOMO-LUMO gap and electronic global quantities (ionization potential (I) and electron affinity (A)) as descriptors.展开更多
This paper presents the performance and characteristics of new-type sulfur tolerant shift catalyst QDB-04 and its industrial side-line test as well as the first-time industrial application in Lunan Chemical Fertilizer...This paper presents the performance and characteristics of new-type sulfur tolerant shift catalyst QDB-04 and its industrial side-line test as well as the first-time industrial application in Lunan Chemical Fertilizer Plant of Shandong in China. The results show that the catalyst has high strength and strength stability, good low temperature activity and stability as well as low potassium bleeding ratio which well meet for the requirements of the methanol plant on catalyst performance in Lunan Chemical Fertilizer Plant.展开更多
Photoinduced electron transfer reaction between the excited state ruthenium (II) polypyridyl complexes and quinones has been investigated in cetyltrimethylammonium bromide using luminescent quenching techniques. The c...Photoinduced electron transfer reaction between the excited state ruthenium (II) polypyridyl complexes and quinones has been investigated in cetyltrimethylammonium bromide using luminescent quenching techniques. The complexes have the absorption and emission maximum in the range 452 - 468 nm and 594 - 617 nm respectively. The static nature of quenching is confirmed from the ground state absorption studies. The association constants for the complexes with quinones are calculated from the Benesi-Hildebrand plots using absorption spectral data. The value of quenching rate constant (kq) is highly sensitive to the nature of the ligand and the quencher, the medium, structure and size of the quenchers. Compared to the aqueous medium, the electron transfer rate is altered in CTAB medium. The oxidative nature of the quenching is confirmed by the formation of Ru3+ ion and quinone anion radical.展开更多
Poly(acrylamide-acrylic acid-dimethyl amino ethylmethacrylate), p(AM-AA-DMAEM) and Poly(acrylamide-acrylic acid)-ethylene diamine tetracetic acid disodium, p(AM-AA)-EDTANa2 were prepared by gamma radiation-induced tem...Poly(acrylamide-acrylic acid-dimethyl amino ethylmethacrylate), p(AM-AA-DMAEM) and Poly(acrylamide-acrylic acid)-ethylene diamine tetracetic acid disodium, p(AM-AA)-EDTANa2 were prepared by gamma radiation-induced template polymerization technique. The prepared polymeric materials were used for the sorption of Ga(III), Cu(II), Ni(II) and Zn(II) in aqueous solution. The effect of pH, weight of resins, metal ion concentrations and contact time on the sorption of these metal ions were studied.展开更多
文摘The reaction of L (MAD) with Cu2+ and Co2+ chlorides affords new metal complexes. The isolated solid complexes were synthesized by two different techniques i.e., chemical and tribochemical methods. Four new complexes were synthesized by direct chemical reactions of MCl2 (M = Co2+ and Cu2+) with MAD in absolute EtOH. The isolated solid complexes were used as starting compounds to synthesize another four new complexes using tribochemical technique by grinding the previous complexes in the solid state with excess KI in agate mortar. The results of the isolated complexes indicate the substitution of the chloride by iodide ions during grinding and extraction of the complexes by a mixture of solvents (EtOH + MeOH). Also, the results suggest that no reduction of Cu2+ or oxidation of Co2+ complexes is observed. The IR spectra of the complexes suggest that L acts in a bidentate manner. Moreover, the results of electronic spectra and magnetic measurements for the chloride and iodide complexes suggest distorted-octahedral and/or tetrahedral for Cu2+ and high-spin octahedral and/or tetrahedral structures around the Co2+ ion, respectively.
文摘The reaction of benzene-1,2,3-tricarboxylate copper(II) trihydrate (Cu<sub>3</sub>(1,2,3-BTC)<sub>2</sub>·3H<sub>2</sub>O) and ethylenediamine (en) gave after recrystallization from methanol at room temperature violet crystalline solid of the polymeric two dimensional material {[Cu<sub>3</sub>(<em>μ</em><sub>3</sub>-1,2,3-BTC)(<em>μ</em><sub>2</sub>-1,2,3-BTC)(en)<sub>3</sub>(OH<sub>2</sub>)<sub>2</sub>(OH)(<em>μ</em><sub>2</sub>-OH<sub>2</sub>)]<sub>2</sub>·5H<sub>2</sub>O·O}<sub>n</sub> (1) as identified by single crystal X-ray diffraction analysis. The compound was also characterized by elemental analysis, FT-IR spectroscopy, UV-vis spectroscopy, thermogravimetric analysis (TGA) and magnetic susceptibility. The molecular structure indicates crystallization in the triclinic space group P-1 with the unit cell parameters a = 12.1205(3) <span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;">Å</span></span></span></span>, b = 12.7026(3) <span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;">Å</span></span></span></span>, c = 13.9890(3) <span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;">Å</span></span></span></span>, <em>α</em> = 75.034(1)<span style="white-space:nowrap;">°</span>, <em>β</em> = 74.957(1)<span style="white-space:nowrap;">°</span>, <em>γ</em> = 68.415(1)<span style="white-space:nowrap;">°</span>. Structural analysis also revealed that the dimeric compound is connected by Cu-O-Cu bridges and the dimer is further converted into a polymeric chain structure through bridging of one benzene-1,2,3-tricarboxylate ligand. Different coordination modes are observed at the copper atom. The Cu atom at the center is octahedral while the two other ones are pentacoordinated. Thermal analysis of the compound showed decomposition processes, while magnetic studies indicated a magnetic susceptibility <em>μ</em> of 3.21 BM.
文摘The kinetics of the periodate oxidation of chromium(III)-complex, [CrIII(NTA)(Ala)(H2O)]-(NTA = Nitrilotriacetate and Ala = ß-alanine) to Cr(VI) have been carried out for the temperature range 15°C - 35°C under pseudo-first order conditions, >>?[complex]. Reaction obeyed first order dependence with respect to and [Cr(III)], and the rate of reaction increases with increasing of pH for the range 3.40 - 4.45. Experimentally, the mechanism of this reaction is found to be consistent with the rate law in which the hydroxo species, [CrIII(NTA)(Ala)(OH)]2- is considerably much more reactive than their conjugate acid. ΔH* and ΔS* have been calculated. It is proposed that electron transfer occurs through an inner-sphere mechanism via coordination of to chromium(III).
文摘Two novel copper complexes (<strong>1,2</strong>) with N,O-donor ligands were synthesized by reaction of copper(II) malonates with 3,3’-bis(pyrazolyl)pentane and 4,4’-trimethylenedipyridine in methanol at moderate temperature. These compounds were characterized by elemental analysis, UV-VIS, IR spectroscopies and powder X-ray diffraction analyses. Compound (<strong>1</strong>) melts at higher temperature (202°C) than compound (<strong>2</strong>) (100<span style="white-space:normal;">°</span>C). The IR spectra showed typical vibrations related to C=N and C=C, characteristic of pyrazolyl and pyridine ligands.
文摘Phenylalanine, isocoumarin and Ochratoxin A (OTA) have been intercalated within the interlayer space of layered double hydroxides. Synthesis of these nanocompounds was achieved via co-precipitation. Their physicochemical properties were studied by element chemical analysis, powder X-ray diffraction, infrared spectroscopy and thermal analyses. The presence of OTA in the interlayer is demonstrated by the study of LC-FD Analysis. On the other hand, these studies allow to check how some of the toxin is on the surface of the nanocomposite.
文摘The aim of this work was to test the adsorption efficiency of copper (II) ions in an aqueous solution on Natural Smectite (NS) and Activated Carbon (AC). The experiments carried out in batch mode made it possible to determine the stirring time, the adsorbent mass, the pH, the initial concentration of copper (II) ions, the isotherms and the adsorption kinetics. It appears that the stirring time was 15 minutes for the AC and 20 minutes for the NS. The adsorption was at maximum for the two adsorbents at optimum pH of 3.5 for a mass of 0.05 g each. The quantity of copper (II) ions adsorbed was 26.6 mg/L for NS and 36.6 mg/g for AC of a concentration of 600 mg/L each. The Langmuir isotherm was the one that best described the adsorption process for the two adsorbents. The adsorption kinetics obtained was that of the pseudo second-order for our two adsorbents. The results obtained showed that these two adsorbents were effective for the adsorption of copper (II) ions in an aqueous solution.
文摘Schiff base derived from 2-aminophenol and 3-formyl-2-hydroxy-6-methoxyquinoline and its Mn(II) and Fe(II) complexes were synthesized and characterized by melting point and decomposition temperature, elemental analysis, molar conductivity, infrared (IR) spectral analysis, atomic absorption spectroscopy (AAS) analysis, solubility test, and magnetic susceptibility. The Fourier-transform infrared spectroscopy (FTIR) spectral data of the Schiff base determined showed <span><span style="font-family:Verdana;">a band at 1622 cm</span><sup><span style="font-family:Verdana;"><span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;">−</span></span></span>1</span></sup><span style="font-family:Verdana;"> and this was assigned to the </span><i><span style="font-family:Verdana;">v </span></i><span style="font-family:Verdana;">(C=N), which is a feature of azomethine group. The same band was observed to shift to lower frequencies 1577 and 1599 cm</span><sup><span style="font-family:Verdana;"><span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;">−</span></span></span>1</span></sup><span style="font-family:Verdana;"> in the complexes suggesting coordination of the Schiff base with the respective metal(II) ions. Molar conductan</span></span><span><span style="font-family:Verdana;">ce values 14.58 and 12.65 Ω</span><sup><span style="font-family:Verdana;"><span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;">−</span></span></span>1</span></sup><span style="font-family:Verdana;"><span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;">∙</span></span></span>cm</span><sup><span style="font-family:Verdana;">2</span></sup><span style="font-family:Verdana;"><span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;">∙</span></span></span>mol</span><sup><span style="font-family:Verdana;"><span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;">−</span></span></span>1</span></sup><span style="font-family:Verdana;"> show that the metal complexes were non-electrolyte in nature. The magnetic susceptibility of the complexes was determined and the gram magnetic susceptibility of the complexes was found to be positive, revealing that they are paramagnetic. The elemental analysis of the complexes for C, N and H determined suggested 1:1 metal to ligand ratio. The result of the antimicrobial studies showed that, the metal(II) complexes exhibited better antibacterial and antifungal activity than the Schiff base.</span></span>
文摘Seven transition metal complexes of Mn<sup>2+</sup>, Ni<sup>2+</sup>, Co<sup>2+</sup>, Cu<sup>2+</sup> and Zn<sup>2+</sup> with 3-aminopyridine (3-APy) as ligand have been synthesized, characterized by different techniques and their antibacterial activities were studied. Molecular modeling calculations were performed using DMOL<sup>3</sup> program in materials studio package which is designed for the realization of large scale density functional theory calculation (DFT). The quantum mechanical and chemical reactivity parameters such as chemical hardness, chemical potential, electronegativity, electrophilicity index and Homo-Lumo energy gap were obtained theoretically and were used to understand the biological activity of the prepared compounds. Some complexes were tested for their in-vitro cytotoxic activity in human lung cancer cell lines (A-549 cell line), and structureactivity relationships were established. In general, the coordination to Co<sup>2+</sup> increased the cytotoxicity while the Ni<sup>2+</sup> complexes show reduced cytotoxic activity compared to the metal-free 3-aminopyridine.
文摘The coordination behavior of 2,3-butanedionemonoxime Girard’s T hydrazone (L<sup>1</sup>) towards Hg<sup>2+</sup> ion has been investigated. The structure of Hg<sup>2+</sup> complex, [Hg(L<sup>1</sup>)Cl]Cl·5H<sub>2</sub>O, is elucidated using elemental analyses, spectral (IR, UV-visible, 1H-NMR and mass) and TGA measurements. IR spectrum suggests that L<sup>1</sup> behaves in a bidentate manner through the azomethine groups. The molecular modeling of L<sup>1</sup> and its Hg<sup>2+</sup> complex has been investigated. The bond lengths, bond angles, HOMO and LUMO have been calculated. The thermal behavior and kinetic parameters are determined using Coats-Redfern method. The use of L<sup>1</sup> for preconcentration and separation via flotation of Hg<sup>2+</sup> complex and determination using cold vapor atomic spectrometry (CVAAS) is described. The effects on the percentage of recovered Hg<sup>2+</sup> by pH of sample solutions, oleic acid (HOL) concentration, Hg<sup>2+</sup> and L<sup>1</sup> concentrations are studied in details. The method is applied for the determination of the total Hg<sup>2+</sup> (mg·mL<sup>-1</sup>) in natural water samples.
文摘Mesoporous molecular sieves, NbFAPO-5 and NbFAPSO-5 were hydrothermally synthesized with AlPO-5 type structure. Characterization of these molecular sieves was performed by X-ray diffraction to determine their structure, ICP-EAS for their elemental composition and infrared spectrometry to access their acidic properties. X-ray diffraction patterns confirmed well AlPO-5 type structure. ICP-EAS analysis confirmed the incorporation of silicon (12.9%), aluminium (15.4%), phosphorous (21.9%), iron (5.62%) and niobium (0.39%) into AlPO-5 framework. Infrared spectrometry analysis showed that both Bronsted and Lewis sites were found in the synthesized samples. The presence of both Bronsted and Lewis acid site led to bifunctional function of NbFAPO-5 and NbFAPSO-5 molecular sieve in promoting both oxidation and esterification reactions. NbFAPSO-5 Bronsted acidity was higher than that of NbFAPO-5 and for Lewis acidity, NbFAPO-5 was higher than that of NbFAPO-5.
文摘The research on sensitizer for dye sensitized solar cells based on (metallo)porphyrin/phthalocyanine materials were reviewed, and experimental design and assembly method were advised. Latest progress and research status of sensitizer dyes based on metalloporphyrins applied in dye sensitized solar cells was summarized. The preparation and construction of sensitizer electrodes and dye sensitized solar cells based on metal organic frameworks (MOFs) of (metallo)porphyrin/phthalocyanine were projected.
文摘Transparent nanostructured BaTiO3 film electrodes were synthesized on conductive substrates from BaTiO3 nanocrystals forming at low temperature. Electrochemical and spectroelectrochemical methods were employed to investigate its properties of band energetics and the trap state at different pH values. The flat band edges greatly depended on the pH value of electrolyte, and the flat band edges were -0.70, -0.92 and -1.20 V vs saturated Ag/AgCl at the pH value of 3.0, 6.8 and 13.0, respectively. The results showed that trap state densities also highly depended on pH. The total trap state densities were 3.73 × 1015, 4.02 × 1015 and 6.48 × 1016 cm-2 at pH value of 3.0, 6.8 and 13.0 respectively with maximum located at -0.36 V, -0.50 V and -0.80 V. The results obtained from CVs were in good agreement with that obtained from the measurements of time resolved currents. The size of the peak potentials in the cyclic voltammograms experiments was increased dramatically with the pH value increasing, indicating that traps were surface-related.
文摘In this paper, the content of water glass before and after adding modifying agent was measured by Trimethylsilyl-gas-chromatography. The experimental results showed that different modulus of water glass could generate different content of mono-silicate acid and oligomeric silicate acid in water glass. After a period of storage, different modulus of water glass led to decrease of silicate content at different levels. Because higher content of Na<sub>2</sub>O in water glass tended to incur the alkaline polymerization, the occurrence of depolymerization of silicate species would lead to an increase of oligomeric silicate species, resulting in a drawback of silicate species content after a period of storage. And contrary to that, lower content of Na<sub>2</sub>O in water glass tended to incur the acidic polymerization. When the modifying agent was added to the newly made water glass, the amount of mono-silicate acid and oligomeric silicate acid also decreased. In modified water glass, the change of each silicate acid species was less than that in unmodified water glass. These results showed that the modifying agent retarded the aging of water glass. It had remarkable significance on the theory and practical application of water glass chemistry.
文摘n this work, we present synthesis of the compounds trans-[Ru(NH<sub>3</sub>)<sub>4</sub>L(bpa)]<sup>2+</sup> where L is pyridine ligands: pyridine (py), isonicotinamide (isn), 4-acetylpyridine (4-acpy) and 4-picoline (4-pic) and 1,2-bis (4-pyridyl) ethane (bpa), their characterization by UV-visible spectroscopy and electrochemical properties. This series shows intense bands in the region between 400 and 515 nm, allocated bands charge transfer (MLCT), the influence of substituents on the pyridine ring (4-acpy and isn), and the interaction between the ligand and the metal, causing a second MLCT band, which is lighter and has more energy. The compound is characterized by spectroscopy by Fourier transform infrared spectroscopy (FTIR). The displacement observed in the symmetrical stretching of ν<sub>s</sub>(CCN) group in the complex compared with the ν<sub>s</sub>(CCN) group in the free ligand is indicative of coordination of the pyridine group to the Ruthenium (II) metallic center. The electrochemical data (cyclic voltammetry) show that reversibility criteria are well defined and formal E<sub>f</sub> potential, indicating the influence of the pyridine ring substituent.
文摘The ligand 1-(1-(pyridin-2-yl)ethylidene)carbonohydrazide (H4L1) and 1-(pyridin-2-ylmethylene)carbonohydrazide (H4L2) were prepared by reaction of carbonohydrazide with 2-acetylpyridine or pyridine carbaldehyde respectively in a reflux methanol solution. The complexes are prepared by reaction of the ligand with the appropriate metal salt. These complexes are well characterized by elemental analysis, IR and UV spectroscopies and their structure were determined by single X-ray diffraction technic. In the crystal of the dinuclear complex [Mn2(H4L1)2(H2O)4]·Cl4, 1) each Mn(II) center is seven coordinated by two nitrogen atom and one carbonyl atom of the one ligand and one nitrogen atom and one carbonyl oxygen atom of another ligand molecule. The coordination sphere is completed by two water molecules. Each of the carbonyl oxygen atom acts as bridge between the two Mn(II) centers. In the mononuclear complex [Co(H4L2)(NO3)(H2O)2]·(NO3);2) the Co(II) center is heptacoordinated. The ligand acts in tridentate fashion through two nitrogen atoms and one carbonyl oxygen atom. Two water molecules lie in the apical positions. One nitrate group acts in bidentate manner while the other nitrate group remains uncoordinated. In both complexes the coordination polyhedral are best described as a pentagonal bipyramid. The molecules are linked together in each case by multiple hydrogen bond interaction resulting in a three-dimensional network. The crystallographic data has been deposited in Cambridge Crystallographic Data Centre [CCDC No. 1944387 (complex 1) and 1944386 (complex 2)].
文摘New transition metal complex of Cobalt(III) of the ligand (E)-3-(1-(2-aminoethylimino)ethyl)-4-hydroxy-2H-chromen-2-one, derived from condensation of ethylene diamine with 3-acetyl-4-hydroxy-chromene-2-one have been synthesized by reaction of cobalt(III) salt and the ligand, in amounts equal to metal-ligand molar ratio of 1:2. Both the Schiff base and the complex of Co(III) were characterized by IR, UV-Vis, 1H NMR- and 13C NMR-spectroscopy techniques. Single crystal X-ray diffraction investigation, at low temperature T = 120 K, shows that the cobalt complex is triclinic P-1, a = 10.426(5) ?, b = 11.3234(2) ?, c = 15.729(5) ?, α(°) = 70.102(4), β(°) = 86.049(4), γ(°) = 82.497(4), Z = 2, and its structure consists of isolated [Co(III)(C13H13N2O3)2]+ complex cations with distorted octahedral geometry, ClO-4 counter anions, acetone solvent and water molecules. The crystal cohesion is stabilized by hydrogen bonds between ligands and water molecules, and ionic interactions between complex cations and counter anions.
文摘The new salt bis(4,5-dihydro-1H-benzo[g]indazole)silver(I) hexafluorophosphate, [Ag(N2H10C11)2]PF6, has been synthesized in methanol at ambient temperature and characterized by elemental and thermal analyses, FTIR and 1HNMR spectroscopies, Rietveld refinement from powder diffraction data and DFT studies. The salt crystallizes in the triclinic space group P-1 with the parameters: a = 7.776 ?, b = 8.676 ?, c = 9.226 ?, α = 69.27° β = 89.86°, γ = 74.50°, V = 558.02 ?3, Z = 1. In the structure, the silver center is coordinated to two nitrogen atoms from two 4,5-dihydro-1H-benzo[g]indazole ligands, forming a centrosymmetric complex cation, [Ag(N2H10C11)2]+, with a linear coordination geometry around the silver center. The hexafluorophosphate ion, , acts as counter anion. The crystal packing is governed by N-H···F and C-H···F hydrogen bonds that interconnect the ionic constituents and Ag···F and Ag···π interactions help for the stabilization of the packing. The optimized structure was obtained at B3LYP/LanL2DZ level in the gas phase. The stability and reactivity of the structure were studied using respectively HOMO-LUMO gap and electronic global quantities (ionization potential (I) and electron affinity (A)) as descriptors.
文摘This paper presents the performance and characteristics of new-type sulfur tolerant shift catalyst QDB-04 and its industrial side-line test as well as the first-time industrial application in Lunan Chemical Fertilizer Plant of Shandong in China. The results show that the catalyst has high strength and strength stability, good low temperature activity and stability as well as low potassium bleeding ratio which well meet for the requirements of the methanol plant on catalyst performance in Lunan Chemical Fertilizer Plant.
文摘Photoinduced electron transfer reaction between the excited state ruthenium (II) polypyridyl complexes and quinones has been investigated in cetyltrimethylammonium bromide using luminescent quenching techniques. The complexes have the absorption and emission maximum in the range 452 - 468 nm and 594 - 617 nm respectively. The static nature of quenching is confirmed from the ground state absorption studies. The association constants for the complexes with quinones are calculated from the Benesi-Hildebrand plots using absorption spectral data. The value of quenching rate constant (kq) is highly sensitive to the nature of the ligand and the quencher, the medium, structure and size of the quenchers. Compared to the aqueous medium, the electron transfer rate is altered in CTAB medium. The oxidative nature of the quenching is confirmed by the formation of Ru3+ ion and quinone anion radical.
文摘Poly(acrylamide-acrylic acid-dimethyl amino ethylmethacrylate), p(AM-AA-DMAEM) and Poly(acrylamide-acrylic acid)-ethylene diamine tetracetic acid disodium, p(AM-AA)-EDTANa2 were prepared by gamma radiation-induced template polymerization technique. The prepared polymeric materials were used for the sorption of Ga(III), Cu(II), Ni(II) and Zn(II) in aqueous solution. The effect of pH, weight of resins, metal ion concentrations and contact time on the sorption of these metal ions were studied.
