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1.
BMC Plant Biol ; 24(1): 605, 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38926865

RESUMEN

Plants spontaneously accumulate γ-aminobutyric acid (GABA), a nonprotein amino acid, in response to various stressors. Nevertheless, there is limited knowledge regarding the precise molecular mechanisms that plants employ to cope with salt stress. The objective of this study was to investigate the impact of GABA on the salt tolerance of eight distinct varieties of bread wheat (Triticum aestivum L.) by examining plant growth rates and physiological and molecular response characteristics. The application of salt stress had a detrimental impact on plant growth markers. Nevertheless, the impact was mitigated by the administration of GABA in comparison to the control treatment. When the cultivars Gemmiza 7, Gemmiza 9, and Gemmiza 12 were exposed to GABA at two distinct salt concentrations, there was a substantial increase in both the leaf chlorophyll content and photosynthetic rate. Both the control wheat cultivars and the plants exposed to salt treatment and GABA treatment showed alterations in stress-related biomarkers and antioxidants. This finding demonstrated that GABA plays a pivotal role in mitigating the impact of salt treatments on wheat cultivars. Among the eight examined kinds of wheat, CV. Gemmiza 7 and CV. Gemmiza 11 exhibited the most significant alterations in the expression of their TaSOS1 genes. CV. Misr 2, CV. Sakha 94, and CV. Sakha 95 exhibited the highest degree of variability in the expression of the NHX1, DHN3, and GR genes, respectively. The application of GABA to wheat plants enhances their ability to cope with salt stress by reducing the presence of reactive oxygen species (ROS) and other stress indicators, regulating stomatal aperture, enhancing photosynthesis, activating antioxidant enzymes, and upregulating genes involved in salt stress tolerance.


Asunto(s)
Regulación de la Expresión Génica de las Plantas , Estrés Salino , Plantones , Triticum , Ácido gamma-Aminobutírico , Triticum/genética , Triticum/efectos de los fármacos , Triticum/crecimiento & desarrollo , Triticum/fisiología , Triticum/metabolismo , Ácido gamma-Aminobutírico/metabolismo , Plantones/genética , Plantones/crecimiento & desarrollo , Plantones/efectos de los fármacos , Plantones/fisiología , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Biomarcadores/metabolismo , Fotosíntesis/efectos de los fármacos , Tolerancia a la Sal/genética , Tolerancia a la Sal/efectos de los fármacos , Clorofila/metabolismo , Antioxidantes/metabolismo
2.
J Biomol Struct Dyn ; : 1-13, 2023 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-37837436

RESUMEN

Drought has emerged as a significant global concern in recent years, leading to a proliferation of research on sorghum, an important drought resistant crop. Consequently, conducting a bibliometric analysis of said publications has the potential to yield insights into current areas of interest and potential avenues for future research. The present study utilized the Web of Science database to gather literature published between the years 2000 and 2022. The search terms 'drought' AND 'sorghum' was employed to identify relevant publications and as a result, 1731 publications were obtained. The bibliometric analysis of the obtained articles was conducted using VOSviewer software (1.6.19). The keyword 'sorghum' was found to have the highest frequency, with a total link strength of 4238. This keyword exhibited a strong association with the terms 'drought' and 'drought tolerance'. The average number of citations for the 100 most-cited articles was 509.2. The journal Crop Science attained the top position with 60 published articles and secured the highest number of citations with a count of 2795. The academic works of Graeme L. Hammer, comprising 40 articles affiliated with the University of Queensland (UQ), have garnered a total of 3612 citations. Similarly, the same university has produced 112 articles that have been cited 5551 times, thereby establishing it as the most frequently cited organization, with Hammer receiving the highest citation count. UQ had a total of 41 collaborators, with a cumulative link strength of 115. The USA has the highest number of articles pertaining to drought and sorghum. The published literature has focused on abiotic stress tolerance, genetic analysis, and physiological traits, among others. It is anticipated that there will be a substantial rise in the quantity of worldwide publications pertaining to drought and sorghum. The USA offered a significant contribution to this emerging field.Communicated by Ramaswamy H. Sarma.

3.
Nanomaterials (Basel) ; 13(6)2023 Mar 09.
Artículo en Inglés | MEDLINE | ID: mdl-36985894

RESUMEN

In this study, the role of selenium nanoparticles (SeNPs, 10 mg·L-1) has been investigated in modulating the negative effects of drought and heat stresses on eight bread wheat (Triticum aestivum L.) genotype seedlings. Those genotypes included Giza-168, Giza-171, Misr-1, Misr-3, Shandweel-1, Sids-1, Sids-12, and Sids-14. The study included six treatments as follows: regular irrigation with 100% Field Capacity (FC) at a temperature of 23 ± 3 °C (T1), drought stress with 60% FC (T2), heat stress of 38 °C for 5 h·day-1 (T3), foliar spray of 10 mg·L-1 of SeNPs only (T4), a combination of drought stress with foliar spray of 10 mg·L-1 of SeNPs (T5), and heat stress with foliar spray of 10 mg·L-1 of SeNPs (T6). The experiment continued for 31 days. Foliar application of SeNPs improved the plant growth, morpho-physiological and biochemical responses, and expression of stress-responsive genes in wheat (T. aestivum L.) seedlings. Overall, morpho-physiological traits such as plant height (PH), shoot fresh weight (SFW), shoot dry weight (SDW), root fresh weight (RFW), and root dry weight (RDW) of wheat genotypes grown under different conditions ranged from 25.37-51.51 cm, 3.29-5.15 g, 0.50-1.97 g, 0.72-4.21 g, and 0.11-1.23 g, respectively. From the morpho-physiological perspective, drought stress had a greater detrimental impact on wheat plants than heat stress, whereas heat stress significantly impacted the expression of stress-responsive genes. Stress responses to drought and heat varied between wheat genotypes, suggesting that different genotypes are more resilient to stress. Exogenous spraying of 10 mg·L-1 of SeNPs improved the photosynthetic pigments, photosynthetic rate, gas exchange, and transpiration rate of wheat plants and enhanced drought and heat tolerance by increasing the activity of antioxidant enzymes including catalase (CAT), ascorbate peroxidase (APX), and superoxide dismutase (SOD) and the expression level of stress-responsive genes. Our results showed that spraying wheat seedlings with 10 mg·L-1 of SeNPs enhanced SOD activity for all genotypes as compared to the control, with the Sids-12 genotype having the highest value (196.43 U·mg-1 FW·min-1) and the Giza-168 genotype having the lowest (152.30 U·mg-1 FW·min-1). The expression of PIP1, LEA-1, HSP70, and HSP90 stress-responsive genes was more significant in tolerant genotypes (Giza-171 and Giza-168) than in sensitive ones (Misr-1 and Misr-3) in response to drought and heat stresses. Under stress conditions, the shoot and root fresh weights, photosynthetic pigment content, stomatal conductance (SC), and transpiration rate (TR) were positively correlated with plant height (PH), while root and shoot dry weights, malondialdehyde (MDA), proline, hydrogen peroxide (H2O2), and APX were negatively correlated. Multivariate analysis and biplot results revealed that genotypes Giza-168, Giza-171, Sids-12, and Sids-14 performed well in both stress situations and were classified as stress-tolerant genotypes. These best genotypes may be employed in future breeding projects as tools to face climate change. This study concluded that various physio-biochemicals and gene expression attributes under drought and heat stress could be modulated by foliar application of SeNPs in wheat genotypes, potentially alleviating the adverse effects of drought and heat stress.

4.
Genes (Basel) ; 14(1)2022 12 22.
Artículo en Inglés | MEDLINE | ID: mdl-36672774

RESUMEN

Wheat (Triticum aestivum L.) is a key food crop, accounting for approximately 765 million tons produced worldwide. The present study evaluated 16 wheat genotypes using 19 morphological and phenological traits, 16 molecular markers (Inter Simple Sequence Repeats and Start Codon Targeted; ISSR and SCoT) and rbcL and matK plastid gene barcoding. The 16 wheat genotypes showed significant genetic variation using the markers assayed. Cell plot of phenological parameters revealed significant differences among the 16-day-old seedlings of wheat genotypes at Z1.1 growth stage. Collectively, W2 genotype had the lowest shoot length (SL), length of first internodes (LFI) and leaf area (LA) values, while W8 genotype had the highest diameter of first internode (DFI) and LA values. Furthermore, W7 genotype had the maximum plant biomass (PB) and leaf width (LW) values. Geometric models grouped wheat kernels into "rounded" and "nearly elongated". Estimates of heritability (H2) for these morphological characters ranged from 4.93 to 100%. The highest H2 values were recorded for root number (RN) (100%) followed by SL (88.72%), LFI (88.30%), LA (87.76%) and Feret diameter (86.68%), while the lowest H2 value was recorded for DFI (4.93%). Furthermore, highly significant genotypic and phenotypic correlations were also observed among those traits. Reproducible fingerprinting profiles and high levels of polymorphism (PPB%) of SCoT (95.46%) and ISSR (82.41%) were recorded, indicating that they are effective tools for detecting genetic variation levels among wheat genotypes. The informativeness of markers were measured through estimation of polymorphic information content (PIC), resolving power (RP) and marker index (MI). The RP and PPB% of SCoT were significantly higher compared to those of ISSR. Comparatively, the two molecular markers were effective for studying genetic diversity among wheat genotypes, but SCoT markers were more informative. Moreover, based on the two chloroplast DNA regions (rbcL and matK), MatK was found to be more reliable for differentiating among T. aestivum genotypes. Taken together, using all the studied attributes, a clear taxonomic relationship can be used to identify T. aestivum species and improve their pragmatic production and development.


Asunto(s)
Variación Genética , Triticum , Variación Genética/genética , Filogenia , Código de Barras del ADN Taxonómico , Marcadores Genéticos/genética , Genotipo
5.
Plants (Basel) ; 10(11)2021 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-34834891

RESUMEN

Barley production is essential in Egypt. In the present study, 15 different six-rowed Egyptian barley cultivars were studied. To differentiate between the different cultivars under study in terms of morphological characteristics and ISSR, molecular characterization reactions were carried out. Moreover, four cultivars (Giza 123, Giza 126, Giza 136, and Giza 138) were selected for further studies using scanning electron microscopy (SEM). Computational analysis of the DNA barcoding sequences of the two plastid markers rbcL and matK was executed, and the results were deposited in the NCBI database. The morphological traits showed low statistical significance among the different cultivars under study via the data collected from two seasons, suggesting that the mean field performance of these Egyptian cultivars may be equal under these conditions. The results showed that the phylogenetic tree was divided into four groups, one of which contained the most closely related genotypes in the genetic distance, including Giza 124, Giza 130, Giza 138, Giza 136, and Giza 137, which converge in the indicative uses of farmers. The seed coat of the studied cultivars was "rugose". The elevation folding of the rugose pattern ranged from 11 ± 1.73 µm (Giza 126) to 14.67 ± 2.43 µm (Giza 123), suggesting variation in seed quality and its uses in feed and the food industry. According to the similarity matrix of ISSR analysis, the highest similarity value (93%) was recorded between Giza 133 and Giza 132, as well as between Giza 2000 and Giza 126. On the other hand, the lowest similarity value (80%) was recorded between Giza 130 and (Giza 133 and Giza 132), indicating that these cultivars were distantly related. Polymorphism information content (PIC) ranged from 0.26 for the primer ISSR UBC 835 to 0.37 for the primers ISSR UBC 814 and ISSR UBC 840. The current study showed that the matK gene is more mutable than the rbcL gene among the tested cultivars.

6.
Comput Biol Chem ; 78: 260-272, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30597437

RESUMEN

Structural and molecular properties of HL, 4-amino-5-(2,2-dichloro-1-methylcyclopropyl)-4H-1,2,4-triazole-3-thiol toward the transition metal ions namely Fe(III), Co(II) and Ni(II) had been studied using elemental analyses, magnetic, electronic, FT- IR, 1H-NMR and Thermal analyses (TGA and DTA). The interpretation of thermal decomposition stages had been evaluated. The computations had been done by software of Gaussian 09W package. The geometries of triazole-thiole ligand and its metal chelates were fully optimized using density functional theory B3LYP method. (DFT)/GENECP level by implementing Def2TZVP basis set was used for Fe, Co and Ni-atoms; and basis set 6-311++G (d, p) was used for remainder atoms. There are no symmetry constrains had been applied during geometry optimization. The mixed basis set was selected due to its flexibility. HOMO and LUMO energy values for chelates, chemical hardness and electronegativity had been calculated. NBO calculations had been done at the same level using (NBO 3.1) program involved in the software of Gaussian 09W for measurement qualitatively the intra-molecular delocalization in systems under investigation. The first 15, 85, 65 and 65 low-lying excited states for ligand and Fe, Co and Ni chelates respectively had been calculated within the vertical linear-response. TD-DFT approximation at the same level of theory was used to calculate the electronic absorption spectra of the studied compounds. Their structures are confirmed by successful correlation between experimental and theoretical calculations. The ligand and its metal chelates had been examined against two bacteria such as Gram-positive (Staphylococcus aureus ATTC 12600), GraM-Negative (Escherichia coli ATTC 11775) and two fungus (Aspergillus flavus and Candida albicans) and molecular docking using Auto Dock tools were utilized.


Asunto(s)
Antibacterianos/farmacología , Antifúngicos/farmacología , Quelantes/farmacología , Complejos de Coordinación/farmacología , Compuestos de Sulfhidrilo/farmacología , Triazoles/farmacología , Antibacterianos/síntesis química , Antibacterianos/química , Antifúngicos/síntesis química , Antifúngicos/química , Aspergillus/efectos de los fármacos , Candida albicans/efectos de los fármacos , Quelantes/síntesis química , Quelantes/química , Complejos de Coordinación/síntesis química , Complejos de Coordinación/química , Teoría Funcional de la Densidad , Escherichia coli/efectos de los fármacos , Ligandos , Pruebas de Sensibilidad Microbiana , Teoría Cuántica , Programas Informáticos , Staphylococcus aureus/efectos de los fármacos , Compuestos de Sulfhidrilo/síntesis química , Compuestos de Sulfhidrilo/química , Temperatura , Triazoles/síntesis química , Triazoles/química
7.
Int J Biol Macromol ; 120(Pt B): 2188-2199, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30009903

RESUMEN

The removal of industrial pollutants from wastewater is important to protect human health and the environment. For this reason, bifunctional hydrogel was synthesized by radiation-induced grafting copolymerization of 2-acrylamido-2-methylpropane-1-sulphonic acid (AMPS) and dimethylaminoethyl methacrylate (DMAEMA) onto starch and subsequent chemical modification of the prepared hydrogel by benzyl chloride. The physical and chemical properties of the hydrogel AMPS co DMAEMA modified with ion-exchange groups were investigated by FT-IR, DSC and SEM techniques. The modified copolymers were examined for the removal of basic dyes, cobalt ions, and phosphate anions from aqueous solution. The maximum adsorption capacities of dye, cobalt and phosphate ions were 600 mg/g, 350 mg/g, and 650 mg/g, respectively at the optimum conditions. The adsorption of dye, Co2+ ions, and phosphate anions onto the hydrogel obeyed both Langmuir and Freundlich models. The adsorption kinetics of dye was found to follow closely the pseudo-first-order kinetic model rather than the pseudo-second-order kinetic model. The kinetic study of Co2+ ions adsorption indicates that it obeys pseudo-second-order kinetic model rather than pseudo-first order one.


Asunto(s)
Hidrogeles/química , Polimerizacion , Almidón/química , Contaminantes Químicos del Agua/aislamiento & purificación , Acrilamidas/química , Adsorción , Alcanosulfonatos/química , Colorantes/química , Colorantes/aislamiento & purificación , Difusión , Concentración de Iones de Hidrógeno , Metales Pesados/química , Metales Pesados/aislamiento & purificación , Metacrilatos/química , Temperatura , Factores de Tiempo , Contaminantes Químicos del Agua/química
8.
Artículo en Inglés | MEDLINE | ID: mdl-25721778

RESUMEN

Novel bisaldehyde-hydrazide Schiff's bases AS1 (2,2'-(ethane-1,2-diylbis(oxy))dibenzaldehyde terephthalohydrazide) and AS2 (N',N'″-(((ethane-1,2-diylbis(oxy))bis(2,1-phenylene))bis(methanylylidene))di(benzohydrazide)) were prepared as new macrocyclic compounds via condensation reactions. AS1 had been prepared by condensation between (2,2'-(ethane-1,2-diylbis(oxy))dibenzaldehyde) bisaldehyde and terephthalohydrazide in a ratio1:1. AS2 had been obtained by condensation between (2,2'-(ethane-1,2-diylbis(oxy))dibenzaldehyde) bisaldehyde and benzohydrazide in ratio 1:2. The structures of AS1 and AS2 were characterized by elemental analysis (EA), mass (MS), FT-IR and (1)H-NMR spectra, and thermal analyses (TG, DTG). The activation thermodynamic parameters such as ΔE(∗), ΔH(∗), ΔS(∗) and ΔG(∗) were calculated from the TG curves using Coats-Redfern method. It is important to investigate their molecular structures to know the active groups and weak bonds responsible for their biological activities. Consequently in the present work, the obtained thermal (TA) and mass (MS) practical results are confirmed by semi-empirical MO-calculations (MOCS) using PM3 procedure. Their biological activities had been tested in vitro against Escherichia coli, Proteus vulgaris, Bacillus subtilis and Staphylococcus aurous bacteria in order to assess their anti-microbial potential.


Asunto(s)
Antibacterianos/química , Benzaldehídos/química , Hidrazinas/química , Bases de Schiff/química , Antibacterianos/síntesis química , Antibacterianos/farmacología , Bacillus subtilis/efectos de los fármacos , Benzaldehídos/síntesis química , Benzaldehídos/farmacología , Escherichia coli/efectos de los fármacos , Hidrazinas/síntesis química , Hidrazinas/farmacología , Modelos Moleculares , Estructura Molecular , Pseudomonas aeruginosa/efectos de los fármacos , Bases de Schiff/síntesis química , Bases de Schiff/farmacología , Estereoisomerismo , Streptococcus pneumoniae/efectos de los fármacos , Termodinámica
9.
Artículo en Inglés | MEDLINE | ID: mdl-25767990

RESUMEN

Novel bis Schiff base ligand, [N1,N3-bis(furan-2-ylmethylene)propane-1,3-diamine], was prepared by the condensation of furan-2-carboxaldehyde with propane-1,3-diamine. Its conformational changes on complexation with transition metal ions [Co(II), Ni(II), Cu(II), Mn(II), Cd(II), Zn(II) and Fe(III)] have been studied on the basis of elemental analysis, conductivity measurements, spectral (infrared, (1)H NMR, electronic), magnetic and thermogravimetric studies. The conductance data of the complexes revealed their electrolytic nature suggesting them as 1:2 (for bivalent metal ions) and 1:3 (for Fe(III) ion) electrolytes. The complexes were found to have octahedral geometry based on magnetic moment and solid reflectance measurements. Thermal analysis data revealed the decomposition of the complexes in successive steps with the removal of anions, coordinated water and bis Schiff base ligand. The thermodynamic parameters were calculated using Coats-Redfern equation. The Anticancer screening studies were performed on human colorectal cancer (HCT), hepatic cancer (HepG2) and breast cancer (MCF-7) cell lines. The antimicrobial activity of all the compounds was studied against Gram negative (Escherichia coli and Proteus vulgaris) and Gram positive (Bacillus vulgaris and Staphylococcus pyogones) bacteria. It was observed that the coordination of metal ion has a pronounced effect on the microbial activities of the bis Schiff base ligand. All the metal complexes have shown higher antimicrobial effect than the free bis Schiff base ligand.


Asunto(s)
Antibacterianos/farmacología , Antineoplásicos/farmacología , Diaminas/química , Furanos/química , Bases de Schiff/síntesis química , Bases de Schiff/farmacología , Temperatura , Antioxidantes/farmacología , Bacterias , Línea Celular Tumoral , Complejos de Coordinación/química , Complejos de Coordinación/farmacología , Conductividad Eléctrica , Espectroscopía de Resonancia por Spin del Electrón , Electrones , Humanos , Ligandos , Fenómenos Magnéticos , Espectrometría de Masas , Pruebas de Sensibilidad Microbiana , Espectroscopía de Protones por Resonancia Magnética , Bases de Schiff/química , Espectrofotometría Infrarroja , Termogravimetría
10.
Spectrochim Acta A Mol Biomol Spectrosc ; 134: 155-64, 2015 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-25016203

RESUMEN

Two novel Schiff's bases (EB1 and L1) as new macrocyclic compounds were prepared via condensation reactions between bisaldehyde (2,2'-(ethane-1,2-diylbis(oxy))dibenzaldehyde): firstly with hydrazine carbothioamide to give (EB1), secondly with 4,6-diaminopyrimidine-2-thiol to give (L1). EB1 has a general formula C18H20N6O2S2 of mole mass=416.520, and IUPAC name ((N,N'Z,N,N'E)-N,N'-(((ethane1,2diylbis(oxy))bis(2,1phenylene))bis(methanylylidene))bis(1hydrazinylmethanethioamide). L1 has a general formula C20H16N4O2S of mole mass=376.10; and IUPAC name 1,2-bis(2-vinylphenoxy)ethane4,6-diaminopyrimidine-2-thiol). The structures of the compounds obtained were characterized based on elemental analysis, FT-IR and (1)H NMR spectra, mass, and thermogravimetric analysis (TG, DTG). The activation thermodynamic parameters, such as, ΔE(*), ΔH(*), ΔS(*) and ΔG(*) were calculated from the TG curves using Coats-Redfern method. It is important to investigate their structures to know the active groups and weak bond responsible for their biological activities. The obtained thermal (TA) and mass (MS) practical results are confirmed by semi-empirical MO-calculation using PM3 procedure, on the neutral and positively charged forms of these novel Schiff bases. Therefore, comparison between MS and TA helps in selection of the proper pathway representing the decomposition of these compounds to give indication about their structures and consequently their biological activities. Their biological activities have been tested in vitro against Escherichia coli, Proteus vulgaris, Bacillissubtilies and Staphylococcus aurous bacteria in order to assess their antimicrobial potential.


Asunto(s)
Antibacterianos/química , Hidrazinas/química , Pirimidinas/química , Bases de Schiff/química , Compuestos de Sulfhidrilo/química , Tioamidas/química , Antibacterianos/farmacología , Técnicas de Química Sintética , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Pruebas de Sensibilidad Microbiana , Modelos Químicos , Estructura Molecular , Espectroscopía Infrarroja por Transformada de Fourier , Termodinámica
11.
Ultrason Sonochem ; 20(5): 1194-202, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23591017

RESUMEN

The present paper deal with the multi-component condensation of 8-hydroxy quinoline, aromatic aldehydes, and sulfone derivatives catalyzed by p-toluenesulfonic acid for the synthesis of a series of 4H-pyrano[3,2-h]quinoline derivatives in ethanol under ultrasonic irradiations. We provide a series of quinoline derivatives containing sulfone moiety interesting for biological screening tests. The reactions were carried out under both conventional and ultrasonic irradiation conditions. In general, improvement in rates and yields were observed when reactions were carried out under sonication compared with classical silent conditions. Also, also, sonochemical reaction give different reaction pathway other than silent reaction. These remarkable effects appeared in sonicated reactions can be reasonably interpreted in terms of acoustic cavitation phenomenon. Structures of the products were established on analytical and spectral data.


Asunto(s)
Aldehídos/química , Compuestos Heterocíclicos con 3 Anillos/síntesis química , Piranos/síntesis química , Quinolinas/química , Quinolinas/síntesis química , Sonicación , Sulfonas/química , Bencenosulfonatos/química , Catálisis , Compuestos Heterocíclicos con 3 Anillos/química , Estructura Molecular , Piranos/química
12.
Spectrochim Acta A Mol Biomol Spectrosc ; 103: 378-87, 2013 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-23266605

RESUMEN

Novel Schiff base (H(2)L, 1,2-bis[(2-(2-mercaptophenylimino)methyl)phenoxy] ethane) derived from condensation of bisaldehyde and 2-aminothiophenol was prepared in a molar ratio 1:2. The ligand and its metal complexes are fully characterized with analytical and spectroscopic techniques. The metal complexes with Cr(III), Mn(II), Fe(III), Co(II), Ni(II), Cu(II), Zn(II) and Th(IV) have been prepared and characterized by elemental analyses, IR and (1)H-NMR spectroscopy, thermal and magnetic measurements. The results suggested that the Schiff base is a bivalent anion with hexadentate OONNSS donors derived from the etheric oxygen (O, O'), azomethine nitrogen (N, N') and thiophenolic sulphur (S, S'). The formulae of the complexes were found to be [ML]·xH(2)O (M=Mn(II) (x=0), Co(II) (x=1), Ni(II), (x=1), Cu(II) (x=2) and Zn(II) (x=0)) and [ML]·nCl (M=Cr(III) (n=1), Fe(III) (n=1) and Th(IV) (n=2)). The thermogravimetric analysis of the complexes shows metal oxide remaining as the final product at 700-1000 °C. Density functional theory at the B3LYP/6-31G(*) level of theory was used to investigate molecular geometry, Mulliken atomic charges and energetics. The synclinal-conformer was found to be responsible for complex formation. The calculation showed that ligand has weak field. Structural deformation and the dihedral angles rotation during complexation were investigated. The binding energy of each complex was calculated. The calculated results are in good agreement with experimental data.


Asunto(s)
Complejos de Coordinación/química , Bases de Schiff/química , Aldehídos/química , Compuestos de Anilina/química , Ligandos , Espectroscopía de Resonancia Magnética , Modelos Moleculares , Espectrofotometría Infrarroja
13.
J Hazard Mater ; 168(1): 137-44, 2009 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-19297095

RESUMEN

Ion exchange adsorbents based on cellulosic fabric wastes carrying sulfonic acid and amine functional groups were synthesized by radiation-induced graft polymerization of glycidyl methacrylate (GMA) with subsequent chemical modification of the epoxy groups of poly-GMA graft chains with sodium sulfite/H(2)SO(4) and triethylamine, respectively. The conversion of epoxy groups into the functional groups was investigated. Factors affecting on grafting process such as radiation dose, monomer concentration and solvent were studied. The synthesized adsorbent and its applications in the removal of different types of hazardous pollutants e.g. acidic dye, cobalt, dichromate and phenols from aqueous solution were also studied.


Asunto(s)
Compuestos Epoxi/química , Residuos Peligrosos/prevención & control , Metacrilatos/química , Contaminantes Químicos del Agua/aislamiento & purificación , Adsorción , Conservación de los Recursos Naturales/métodos , Compuestos Epoxi/efectos de la radiación , Residuos Industriales , Intercambio Iónico , Metacrilatos/efectos de la radiación , Soluciones , Textiles
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