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1.
Acta Radiol ; : 2841851241249161, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38751050

RESUMO

BACKGROUND: Advances in molecular imaging strategies have had an effect on precise diagnosis and treatment. Research has been intensified to develop more effective and versatile radiopharmaceuticals to uplift diagnostic efficiency and, consequently, the treatment. PURPOSE: To label the flutamide (FLUT) coupled with diethylenetriamine pentaacetate (DTPA) with technetium-99 m (99mTc) and to evaluate its binding efficiency with rhabdomyosarcoma (RMS) cancer cells. MATERIAL AND METHODS: Radiolabeling of FLUT with 185 MBq freshly eluted 99mTcO4-1 was carried out via DTPA bifunctional chelating agent using stannous chloride reducing agent at pH 5. The labeled compound was assessed for its purity using chromatography analysis, stability in saline and blood serum, AND charge using paper electrophoresis. Normal biodistribution was studied using a mouse model, while binding affinity with RMS cancer cells was studied using an internalization assay. The in vivo accumulation of RMS cancer cells in a rabbit model was monitored using a SPECT gamma camera. RESULTS: Radiolabeling reaction displayed a pharmaceutical yield of 97% and a stability assay showed >95% intact radiopharmaceutical up to 6 h in saline and blood serum. In vitro internalization studies showed the potential of [99mTc]DTPA-FLUT to enter into cancer cells. This biodistribution study showed rapid blood clearance and minimum uptake by body organs, and scintigraphy displayed the [99mTc]DTPA-FLUT uptake by lesion, induced by RMS cancer cell lines in rabbit. CONCLUSION: Stable, newly developed [99mTc]DTPA-FLUT seeks its way to internalize into RMS cancer cells, indicating it could be a potential candidate for the diagnosis of RMS cancer.

2.
RSC Adv ; 14(3): 1890-1901, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38192328

RESUMO

In this paper, we present a comprehensive analysis of HCl-HCl interactions, including QZVPP calculations, energy fitting, conformation validation, and the determination of the second virial coefficient B using improved Lennard-Jones (ILJ) potential parameters. To acquire accurate interaction energies, initial QZVPP calculations are performed on approximately 1851 randomly generated HCl-HCl conformations. Then, these energies are used to fit an improved Lennard-Jones potential energy surface, allowing for a robust description of HCl-HCl interactions. The ILJ potential parameters are then used to validate particular HCl dimer conformations, ensuring their stability and consistency with experimental observations. The correlation between calculated and experimental conformations strengthens the validity of the ILJ potential parameters. In addition, the second viral coefficient B is calculated at various temperatures using the ILJ potential. The obtained B values are compared to experimental data, demonstrating close agreement, and validating the ILJ potential's ability to accurately capture the intermolecular interactions and gas-phase behavior of the HCl-HCl system. The results of this study demonstrate the effective implementation of QZVPP calculations, energy fitting, and ILJ potential parameters in validating HCl-HCl conformations and accurately determining the second virial coefficient B. The high degree of concordance between calculated B values and experimental data demonstrates the validity of the ILJ potential and its suitability for modeling HCl-HCl interactions. This research contributes to a greater comprehension of HCl-HCl interactions and their implications for numerous chemical and atmospheric processes. The validated conformations, energy fitting method, and calculated second virial coefficients provide valuable instruments for future research and pave the way for more accurate modeling and simulations of HCl-HCl systems.

3.
RSC Adv ; 14(6): 3782-3789, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38274172

RESUMO

Employing a combination of Density Functional Theory (DFT) calculations and Molecular Dynamics (MD) simulations, the adsorption of molecular hydrogen (H2) on Be3Al2(SiO3)6-beryl, a prominent silicate mineral, has been studied. The crystal structure of beryl, which consists of interconnected tetrahedral and octahedral sites, provides a fascinating framework for comprehending H2 adsorption behavior. Initial investigation of the interaction between H2 molecules and the beryl surface employed DFT calculations. We identified favorable adsorption sites and gained insight into the binding mechanism through extensive structural optimizations and energy calculations. H2 molecules preferentially adsorb on the exposed oxygen atoms surrounding the octahedral sites, producing weak van der Waals interactions with the beryl surface, according to our findings. To further investigate the dynamic aspects of H2 adsorption, MD simulations employing a suitable force field were conducted. To precisely represent interatomic interactions within the Be3Al2(SiO3)6-beryl-H2 system, the force field parameters were meticulously parameterized. By subjecting the system to a variety of temperatures, we were able to obtain valuable information about the stability, diffusion, and desorption kinetics of H2 molecules within the beryl structure. The comprehensive understanding of the H2 adsorption phenomenon on Be3Al2(SiO3)6-beryl is provided by the combined DFT and MD investigations. The results elucidate the mechanisms underlying H2 binding, highlighting the role of surface oxygen atoms and the effect of temperature on H2 dynamics. This research contributes to a fundamental understanding of hydrogen storage and release in beryllium-based silicates and provides valuable guidance for the design and optimization of materials for hydrogen storage, catalysis, gas separation, sensing and environmental applications.

4.
RSC Adv ; 13(44): 30937-30950, 2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37876651

RESUMO

Molecular hydrogen (H2) adsorption plays a crucial role in numerous applications, including hydrogen storage and purification processes. Understanding the interaction of H2 with porous materials is essential for designing efficient adsorption systems. In this study, we investigate H2 adsorption on CHA-zeolite using a combination of density functional theory (DFT) and force field-based molecular dynamics (MD) simulations. Firstly, we employ DFT calculations to explore the energetic properties and adsorption sites of H2 on the CHA-zeolite framework. The electronic structure and binding energies of H2 in various adsorption configurations are analyzed, providing valuable insights into the nature of the adsorption process. Subsequently, force field methods are employed to perform extensive MD simulations, allowing us to study the dynamic behavior of H2 molecules adsorbed on the CHA-zeolite surface. The trajectory analysis provides information on the diffusion mechanisms and mobility of H2 within the porous structure, shedding light on the transport properties of the adsorbed gas. Furthermore, the combination of DFT and MD results enables us to validate and refine the force field parameters used in simulations, improving the accuracy of the model, and enhancing our understanding of the H2-CHA interactions. Our comprehensive investigation into molecular hydrogen adsorption on CHA-zeolite using density functional theory and molecular dynamics simulations yields valuable insights into the fundamental aspects of the adsorption process. These findings contribute to the development of advanced hydrogen storage and separation technologies, paving the way for efficient and sustainable energy applications.

5.
RSC Adv ; 13(42): 29632-29644, 2023 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-37822660

RESUMO

Iron-nickel bimetallic nanoparticles (Fe-Ni BMNPs) are prepared by combining two different metals by using the bottom-up approach. The resulting material has entirely different properties as compared to both the metals. The product is examined by using different analytical instruments such as.; scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray diffraction (XRD), MDIJADE, ORIGIN pro to characterize their morphology, crystallinity and elemental composition and the final data has been statistically analyzed. SEM findings show that most nanoparticles are irregular in form and range in size from 10 nm to 100 nm. The findings of the TEM verified that the particles between 10 nm and 50 nm are irregular in size shape. The products acquired utilized as a fuel additive to monitor oil effectiveness by studying various parameters. The degradation of methylene blue dye depends directly on the concentration of the nanocatalyst. Different parameters also use the freshly prepared bimetallic nanocatalyst to investigate the efficacy of the kerosene fuel. By adding a tiny quantity of the nanocatalyst, the value of the flash point and fire point is significantly reduced. The nanocatalyst does not affect the cloud point and pour point to a large extent. The bimetallic nanocatalyst therefore has very excellent catalytic characteristics.

6.
J Phys Chem A ; 127(30): 6175-6185, 2023 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-37478471

RESUMO

N2O, or nitrous oxide, is an important greenhouse gas with a significant impact on global warming and climate change. To accurately model the behavior of N2O in the atmosphere, precise representations of its intermolecular force fields are required. First principles quantum mechanical calculations followed by appropriate fitting are commonly used to establish such force fields. However, fitting such force fields is challenging due to the complex mathematical functions that describe the molecular interactions of N2O. As such, ongoing research is focused on improving our understanding of N2O and developing more accurate models for use in climate modeling and other applications. In this study, we investigated the strength of the intermolecular interactions in the N2O-N2O dimer using the coupled-cluster theory with single, double, and perturbative triple excitation [CCSD(T)] method with the def2-QZVPP basis set. Our calculations provided a detailed understanding of the intermolecular forces that govern the stability and structure of the N2O dimer. We found that the N2O-N2O dimer is stabilized by a combination of van der Waals forces and dipole-dipole interactions. The calculated interaction energy between the two N2O molecules in the dimer was found to be -5.09 kcal/mol, which is in good agreement with previous theoretical and experimental results. Additionally, we analyzed the molecular properties of the N2O-N2O dimer, including its geometry and charge distribution. Our calculations provide a comprehensive understanding of the intermolecular interactions in the N2O-N2O dimer using the CCSD(T) method with the def2-QZVPP basis set by using the improved Lennard-Jones interaction potential method. These results can be used to improve our understanding of atmospheric chemistry and climate modeling, as well as to aid in the interpretation of experimental data.

7.
J Phys Chem A ; 127(26): 5591-5601, 2023 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-37350188

RESUMO

We have investigated the adsorption potential of N2O (nitrous oxide) over graphene. To do this, we utilized various methods and techniques to calculate the potential of N2O over the graphene surface. We performed density functional theory (DFT) calculations for different conformations of N2O on the graphene surface, including parallel, N-up, and O-up and random (∼1000) orientations. We used different force field methods (significantly Improved Lennard-Jones potential) to obtain the best interaction potential that could accurately describe the N2O-graphene adsorption. This involves evaluating the system's potential energy as a function of distance and orientation between the N2O molecule and the graphene surface. By comparing the results of different potential methods, we aimed to identify the most appropriate one that could best describe the adsorption behavior of N2O on graphene. The ultimate goal of the study was to gain insights into the fundamental mechanisms and energetics of N2O adsorption on graphene, which could be useful for a wide range of applications in areas such as catalysis, sensing, and energy storage.

8.
Spectrochim Acta A Mol Biomol Spectrosc ; 279: 121487, 2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-35691166

RESUMO

All-small-molecule acceptors (ASMAs) are considered as well-defined molecular structures with good sustainability and processability. Although these acceptor molecules did not exhibit high power conversion efficiency (PCE) as compared to polymer solar cells, a lot of research is yet to be focused on the development of ASMAs. In this report, a new series of ASMAs (ZMY1 to ZMY5) has been designed by end-capped alteration of recently synthesized ZR-Si4 molecule (PCE = 10.10%). Photovoltaic, optoelectronic and geometric parameters of the newly designed molecules have been investigated through DFT and TD-DFT approaches. Additionally, power conversion efficiency along with fill factor (FF) percentage has been computed for the designed molecules. Enhanced open circuit voltage (Voc) allows PCE at around 18.25 % which is better than the experimentally synthesized ZR-Si4 molecule. Additionally, the high mobility of electrons and hole between metal electrodes also suggested that the designed molecules are effective candidates for the development of efficient organic solar cell (OSC) applications.

9.
Inorg Chem ; 60(14): 10837-10847, 2021 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-34231358

RESUMO

Emission of harmful pollutants from different sources into the environment is a major problem nowadays. Organochlorine pesticides such as DDT (C14H9Cl5) are toxic, bio-accumulative, and regularly seen in water bodies, air, biota, and sediments. Various systems can be considered for minimizing the DDT (dichloro-diphenyl-trichloroethane) pollution. However, due to simplicity and acceptability, the adsorption method is the most popular method. Adsorption is gradually employed for the removal of both organic and inorganic pollutants found in soil and water. Thus, in this regard, efforts are being made to design inorganic nanoclusters (B12N12) encapsulated with late transition metals (Zn, Cu, Ni, Co, and Fe) for effective adsorption of DDT. In this context, detailed thermodynamics and quantum chemical study of all the designed systems have been carried out with the aid of density functional theory. The adsorption energy of DDT on metals cocooned in a nanocluster is found to be higher, and better adsorption energy values as compared to that of the pristine B12N12-DDT nanocluster have been reported. Further, analysis of the dipole moment, frontier molecular orbitals, molecular electrostatic potential plots, energy band gap, QNBO, and Fermi level suggested that the late-transition-metal-encapsulated inorganic B12N12 nanoclusters are efficient candidates for effective DDT adsorption. Lastly, the study of global descriptors of reactivity confirmed that the designed quantum mechanical systems are quite stable in nature with a good electrophilic index. Therefore, the recommendation has been made for these novel kinds of systems to deal with the development of DDT sensors.


Assuntos
DDT/química , DDT/isolamento & purificação , Poluentes Ambientais/química , Poluentes Ambientais/isolamento & purificação , Nanoestruturas/química , Teoria Quântica , Elementos de Transição/química , Adsorção , Modelos Moleculares , Conformação Molecular
10.
Inorg Chem ; 60(4): 2816-2828, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33525872

RESUMO

The increasing demand for energy storage materials has gained considerable attention of scientific community toward the development of hydrogen storage materials. Hydrogen has become more important, as it not only works efficiently in different processes but is also used as an alternative energy resource whenever it is combined with a cell technology like fuel cell. Herein, efforts are being made to develop efficient hydrogen storage materials based on alkaline earth metal (beryllium, magnesium, and calcium)-encapsulated B12N12 nanocages. Quantum chemical calculations were performed using density functional theory (DFT) and time-dependent DFT at B3LYP/6-31G(d,p) and CAM-B3LYP/6-311+G(d,p) levels of theory for all the studied systems. The adsorption energies of Be-B12N12, Mg-B12N12, and Ca-B12N12 systems suggested that Mg and Ca are not fitted accurately in the cavity of nanocages because of their large size. However, H2 adsorbed efficiently on the metal-encapsulated systems with high adsorption energy values. Furthermore, dipole moment and QNBO (Charges-Natural Bond Orbital) calculations suggested that a greater charge separation is seen in H2-adsorbed metal-encapsulated systems. The molecular electrostatic potential analysis also unveiled the different charge sites in the studied systems and also demonstrated the charge separation upon hydrogen adsorption on metal-encapsulated systems. Partial density of states analysis was performed in the support of frontier molecular orbital distribution that indicates the narrow highest occupied molecular orbital-lowest unoccupied molecular orbital energy gap in hydrogen-adsorbed metal-encapsulated systems. Results of all analyses and global descriptions of reactivity suggested that the designed H2-adsorbed metal-encapsulated B12N12 systems are efficient systems for designing future hydrogen storage materials. Thus, these novel kinds of systems for efficient hydrogen storage purposes have been recommended.

11.
Spectrochim Acta A Mol Biomol Spectrosc ; 245: 118938, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-32971344

RESUMO

Chrysene core containing fused ring acceptor materials have remarkable efficiency for high performance organic solar cells. Therefore, present study has been carried out with the aim to design chrysene based novel Z-shaped electron acceptor molecules (Z1-Z6) from famous Z-shaped photovoltaic material FCIC (R) for organic photovoltaic applications. End-capped engineering at two electron-accepting end groups 1,1-dicyanomethylene-3-indanone of FCIC is made with highly efficient end-capped acceptor moieties and impact of end-capped modifications on structure-property relationship, photovoltaic and electronic properties of newly designed molecules (Z1-Z6) has been studied in detail through DFT and TDDFT calculations. The efficiencies of the designed molecules are evaluated through energy gaps, exciton binding energy along with transition density matrix (TDM) analysis, reorganizational energy of electron and hole, absorption maxima and open circuit voltage of investigated molecules. The designed molecules exhibit red-shift and intense absorption in near-infrared region (683-749 nm) of UV-Vis-NIR absorption spectrum with narrowing of HOMO-LUMO energy gap from 2.31 eV in R to 1.95 in eV in Z5. Moreover, reduction in reorganization energy of electron from 0.0071 (R) to 0.0049 (Z5), and enhancement in open circuit voltage from 1.08 V in R to 1.20 V in Z5 are also observed. Twisted Z-shape of designed molecules prevents self-aggregation that facilitates miscibility of donor and acceptor. Low values of binding energy, excitation energy, and reorganizational energy (electron and hole) suggest that novel designed molecules offer high charge mobilities as compared to FCIC. Our findings indicate that these novel designed molecules can display better photovoltaic parameters and are suitable candidates if used in organic solar cells.

12.
Chemistry ; 27(12): 4197-4210, 2021 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-33210769

RESUMO

Perovskite solar cells have gained immense interest from researchers owing to their good photophysical properties, low-cost production, and high power conversion efficiencies. Hole transport materials (HTMs) play a dominant role in enhancing the power conversion efficiencies (PCEs) and long diffusion length of holes and electrons in perovskite solar cells. In hole transport materials, modification of π-linkers has proved to be an efficient approach for enhancing the overall PCE of perovskite solar cells. In this work, π-linker modification of a recently synthesized H-Bi molecule (R) is achieved with novel π-linkers. After structural modifications, ten novel HTMs (HB1-HB10) with a D-π-D backbone are obtained. The structure-property relationship, and optoelectronic and photovoltaic characteristics of these newly designed hole transport materials are examined comprehensively and compared with reference molecules. In addition, different geometric parameters are also examined with the assistance of density functional theory (DFT) and time-dependent DFT. All the designed molecules exhibit narrow HOMO-LUMO energy gaps (Eg =2.82-2.99 eV) compared with the R molecule (Eg =3.05 eV). The designed molecules express redshifting in their absorption spectra with low values of excitation energy, which in return offer high power conversion efficiencies. Further, density of states and molecular electrostatic potential analysis is performed to locate the different charge sites in the molecules. The reorganizational energies of holes and electrons are found to have good values, suggesting that these novel designed molecules are efficient hole transport materials for perovskite solar cells. In addition, the low binding energy values of the designed molecules (compared with R) offer high current charge density. Finally, complex study of HB9:PC61 BM is also undertaken to understand the charge transfer between the molecules of the complex. The results of all analyses advocate that these novel designed HTMs are promising candidates for the construction of future high-performance perovskite solar cells.

13.
ACS Omega ; 5(37): 24125-24137, 2020 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-32984735

RESUMO

This work was inspired by a previous report [Janjua, M. R. S. A. Inorg. Chem. 2012, 51, 11306-11314] in which the optoelectronic properties were improved with an acceptor bearing heteroaromatic rings. Herein, we have designed four novel Y-series non-fullerene acceptors (NFAs) by end-capped acceptor modifications of a recently synthesized 15% efficient Y21 molecule for better optoelectronic properties and their potential use in solar cell applications. Density functional theory (DFT) along with time-dependent density functional theory (TDDFT) at the B3LYP/6-31G(d,p) level of theory is used to calculate the band gap, exciton binding energy along with transition density matrix (TDM) analysis, reorganizational energy of electrons and holes, and absorption maxima and open-circuit voltage of investigated molecules. In addition, the PM6:YA1 complex is also studied to understand the charge shifting from the donor polymer PM6 to the NFA blend. Results of all parameters suggest that the DA'D electron-deficient core and effective end-capped acceptors in YA1-YA4 molecules form a perfect combination for effective tuning of optoelectronic properties by lowering frontier molecular orbital (FMO) energy levels, reorganization energy, and binding energy and increasing the absorption maximum and open-circuit voltage values in selected molecules (YA1-YA4). The combination of extended conjugation and excellent electron-withdrawing capability of the end-capped acceptor moiety in YA1 makes YA1 an excellent organic solar cell (OSC) candidate owing to promising photovoltaic properties including the lowest energy gap (1.924 eV), smallest electron mobility (λe = 0.0073 eV) and hole mobility (λh = 0.0083 eV), highest λmax values (783.36 nm (in gas) and 715.20 nm (in chloroform) with lowest transition energy values (E x) of 1.58 and 1.73 eV, respectively), and fine open-circuit voltage (V oc = 1.17 V) with respect to HOMOPM6-LUMOacceptor. Moreover, selected molecules are observed to have better photovoltaic properties than Y21, thus paving the way for experimentalists to look for future developments of Y-series-based highly efficient solar cells.

14.
J Water Health ; 16(5): 773-781, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30285958

RESUMO

A simple co-precipitation technique is proposed for synthesis of tin oxide (SnO2) microrods. Stannous chloride and urea were used during synthesis. X-ray powder diffraction (XRD) analysis revealed that the annealed product consists of SnO2 microrods having tetragonal unit cells, while scanning electron microscopy (SEM) analysis revealed the rod-like morphology of a synthesized product. These synthesized microrods are used as photocatalyst for the degradation of reactive black 5 (RB5). Degradation kinetics of RB5 are monitored under daylight in different concentrations of hydrogen peroxide (H2O2) and catalyst. The percentage of RB5 conversion is also calculated at various concentrations of hydrogen peroxide and catalyst which demonstrate that RB5 shows high catalytic degradation at high concentrations of hydrogen peroxide and catalyst.


Assuntos
Peróxido de Hidrogênio , Naftalenossulfonatos/química , Processos Fotoquímicos , Compostos de Estanho/química , Catálise , Modelos Químicos , Difração de Raios X
15.
J Am Chem Soc ; 139(50): 18397-18405, 2017 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-29161810

RESUMO

A chemical cosubstitution strategy was implemented to design potential ultraviolet (UV) and deep-UV nonlinear optical (NLO) materials. Taking the classic ß-BaB2O4 as a maternal structure, by simultaneously replacing the Ba2+ and [B3O6]3- units with monovalant (K+), divalent (alkaline earth metal), trivalent (rare-earth metal, Bi3+) ions, and the [B5O10]5- clusters through two different practical routes, 12 new mixed-metal noncentrosymmetric borates K7MIIRE2(B5O10)3 (MII = Ca, Sr, Ba, K/RE0.5; RE = Y, Lu, Gd) as well as K7MIIBi2(B5O10)3 (MII = Pb, Sr) were successfully designed and synthesized as high-quality single crystals. The selected K7CaY2(B5O10)3, K7SrY2(B5O10)3, and K7BaY2(B5O10)3 compounds were subjected to experimental and theoretical characterizations. They all exhibit suitable second-harmonic generation (SHG) responses, as large as that of commercial KH2PO4 (KDP), and also exhibit short UV cutoff edges. These results confirm the feasibility of this chemical cosubstitution strategy to design NLO materials and that the three selected crystals may have potential application as UV NLO materials.

16.
Chem Cent J ; 11(1): 49, 2017 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-29086833

RESUMO

Morphologically controlled synthesis of ferric oxide nano/micro particles has been carried out by using solvothermal route. Structural characterization displays that the predominant morphologies are porous hollow spheres, microspheres, micro rectangular platelets, octahedral and irregular shaped particles. It is also observed that solvent has significant effect on morphology such as shape and size of the particles. All the morphologies obtained by using different solvents are nearly uniform with narrow size distribution range. The values of full width at half maxima (FWHM) of all the products were calculated to compare their size distribution. The FWHM value varies with size of the particles for example small size particles show polydispersity whereas large size particles have shown monodispersity. The size of particles increases with decrease in polarity of the solvent whereas their shape changes from spherical to rectangular/irregular with decrease in polarity of the solvent. The catalytic activities of all the products were investigated for both dry and wet processes such as thermal decomposition of ammonium per chlorate (AP) and reduction of 4-nitrophenol in aqueous media. The results indicate that each product has a tendency to act as a catalyst. The porous hollow spheres decrease the thermal decomposition temperature of AP by 140 °C and octahedral Fe3O4 particles decrease the decomposition temperature by 30 °C. The value of apparent rate constant (kapp) of reduction of 4-NP has also been calculated.

17.
Chem Cent J ; 10: 5, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26848308

RESUMO

BACKGROUND: Carica papaya is a well known medicinal plant used in the West and Asian countries to cope several diseases. Patients were advised to eat papaya fruit frequently during dengue fever epidemic in Pakistan by physicians. This study was conducted to establish Polyphenols, flavonoids and antioxidant potential profile of extracts of all major parts of the C. papaya with seven major solvents i.e. water, ethanol, methanol, n-butanol, dichloromethane, ethyl acetate, and n-hexane. RESULTS: TPC, TFC, antioxidant and antibacterial potential were determined using different aqueous and organic solvents in addition to the determination of trace element in leaves, pulp and peel of C. papaya. Total soluble phenolics and flavonoids were found in promising quantity (≈66 mg GAE/g) especially in case of methanol and ethanol extracts. Antioxidant activity using DPPH free radical scavenging assay indicated leaves, bark, roots and pulp extracts showed >75.0 % scavenging potential while leaves and pulp showed 84.9 and 80.9 % inhibition of peroxidation, respectively. Reducing power assay showed leaves, pulp and roots extracts active to reduce Fe(3+) to Fe(2+) ions. The antibacterial study showed pulp extract is the best to cope infectious action of bacteria. CONCLUSION: This study was conducted to test the medicinal profile of all parts of C. papaya by extracting secondary metabolites with organic and aqueous solvents. Ethanol and methanol both were found to be the best solvents of choice to extract natural products to get maximum medicinal benefits and could be used to medicinal formulation against different infectious diseases.Graphical abstractMedicinal evaluation of different parts of C. papaya.

18.
Phys Chem Chem Phys ; 16(37): 20089-96, 2014 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-25132531

RESUMO

In this work, a potential semiorganic nonlinear optical candidate NH4B[D-(+)-(C4H4O5)]2·H2O (NBC) has been studied using Density Functional Theory. The origin of the second harmonic generation (SHG) effect of NBC crystals for the NH4B[D-(+)-(C4H4O5)]2·H2O molecular complex is explained by employing a combination of the density of states, SHG density and molecular orbital analysis. It reveals a way in which the organic and ammonium groups affect the SHG processes in a significantly different manner in the crystals and the molecular complex. In particular, the role of hydrogen bonding interaction in influencing the electronic structure and nonlinear optical properties is explicitly identified and explained.

19.
Acta Chim Slov ; 61(2): 382-90, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25125122

RESUMO

In this study we have used density functional theory (DFT) to calculate nonlinear optical properties and simulate the UV-VIS absorption spectra of ruthenium acetylide complexes.Among the studied systems, system 4 has shown highest non-linear optical properties (a = 72.92 × 10(-24)esu and b = 76.32 × 10(-30)esu).New compounds have been theoretically designed by the extension of conjugation length and substitution of electron withdrawing atom/groups as acceptor on system 4. All designed compounds show intense band due to metal-to-ligand charge transfer (MLCT).Second-order polarizabilityof new design compounds was remarkablyhigh as compared to system 4 (123.35 × 10(-30)to 360.23 × 10(-30)esu). Effect of acceptors was more prominent than pi-spacers. Results of theoretical investigation indicate that all systems should be excellent non-linear optical materials.

20.
Inorg Chem ; 51(21): 11306-14, 2012 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-23075454

RESUMO

This work was inspired by a previous report (Janjua et al. J. Phys. Chem. A 2009, 113, 3576-3587) in which the nonlinear-optical (NLO) response strikingly improved with an increase in the conjugation path of the ligand and the nature of hexamolybdates (polyoxometalates, POMs) was changed into a donor by altering the direction of charge transfer with a second aromatic ring. Herein, the first theoretical framework of POM-based heteroaromatic rings is found to be another class of excellent NLO materials having double heteroaromatic rings. First hyperpolarizabilities of a large number of push-pull-substituted conjugated systems with heteroaromatic rings have been calculated. The ß components were computed at the density functional theory (DFT) level (BP86 geometry optimizations and LB94 time-dependent DFT). The largest ß values are obtained with a donor (hexamolybdates) on the benzene ring and an acceptor (-NO(2)) on pyrrole, thiophene, and furan rings. The pyrrole imido-substituted hexamolybdate (system 1c) has a considerably large first hyperpolarizability, 339.00 × 10(-30) esu, and it is larger than that of (arylimido)hexamolybdate, calculated as 0.302 × 10(-30) esu (reference system 1), because of the double aromatic rings in the heteroaromatic imido-substituted hexamolybdates. The heteroaromatic rings act as a conjugation bridge between the electron acceptor (-NO(2)) and donor (polyanion). The introduction of an electron donor into heteroaromatic rings significantly enhances the first hyperpolarizabilities because the electron-donating ability is substantially enhanced when the electron donor is attached to the heterocyclic aromatic rings. Interposing five-membered auxiliary fragments between strong donor (polyanion) or acceptor (-NO(2)) groups results in a large computed second-order NLO response. The present investigation provides important insight into the NLO properties of (heteroaromatic) imido-substituted hexamolybdate derivatives because these compounds exhibit enhanced hyperpolarizabilities compared to typical NLO arylimido hexamolybdates and heterocyclic aromatic rings reported in the literature.

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