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1.
PLoS One ; 15(6): e0234053, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32484834

RESUMO

The efficient (site-specific) management of soil nutrients is possible by understanding the spatial variability in distribution of phyto-available nutrients (here after called available nutrients) and identifying the soil management zones (MZs) of agricultural landscapes. There is need for delineating soil MZs of agricultural landscapes of the world for efficient management of soil nutrients in order to obtain sustainability in crop yield. The present study was, therefore, undertaken to understand the spatial distribution pattern of available micronutrients (zinc (Zn), boron (B), iron (Fe), manganese (Mn) and copper (Cu)), available sulphur (S), and soil properties (soil acidity (pH), electrical conductivity (EC) and organic carbon (SOC) content) in soils of intensively cultivated Indo-Gangetic Plain (IGP) of India and to delineate soil MZs for efficient management of soil nutrients. Totally, 55101 soil samples from 0-15 cm depth were obtained from 167 districts of IGP during 2014 to 2017 and were analysed for different soil parameters. Soil pH, EC and SOC content varied from 4.44 to 9.80, 0.02 to 2.13 dS m-1 and 0.10 to 1.99%, respectively. The concentration of available Zn, B, Fe, Mn, Cu and S varied from 0.01 to 3.27, 0.01 to 3.51, 0.19 to 55.7, 0.05 to 49.0, 0.01 to 5.29 and 1.01 to 108 mg kg-1, respectively. Geostatistical analysis resulted in varied distribution pattern of studied soil parameters with moderate to strong spatial dependence. The extent (% area) of nutrient deficiencies in IGP followed the order: S > Zn > B > Mn > Cu > Fe. Principal component analysis and fuzzy c-means clustering produced six distinctly different soil MZs of IGP for implementation of zone-specific soil nutrient management strategies for attaining sustainability in crop yield. The developed MZ maps could also be utilized for prioritization and rationalization of nutrients supply in IGP of India.


Assuntos
Monitoramento Ambiental , Micronutrientes/análise , Solo/química , Análise Espacial , Enxofre/análise , Índia , Chuva , Estatística como Assunto
2.
Soft Matter ; 13(7): 1481-1492, 2017 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-28125114

RESUMO

Biologically relevant monolayer and bilayer films often consist of micron-scale high viscosity domains in a continuous low viscosity matrix. Here we show that this morphology can cause the overall monolayer fluidity to vary by orders of magnitude over a limited range of monolayer compositions. Modeling the system as a two-dimensional suspension in analogy with classic three-dimensional suspensions of hard spheres in a liquid solvent explains the rheological data with no adjustable parameters. In monolayers with ordered, highly viscous domains dispersed in a continuous low viscosity matrix, the surface viscosity increases as a power law with the area fraction of viscous domains. Changing the phase of the continuous matrix from a disordered fluid phase to a more ordered, condensed phase dramatically changes the overall monolayer viscosity. Small changes in the domain density and/or continuous matrix composition can alter the monolayer viscosity by orders of magnitude.

3.
Spectrochim Acta A Mol Biomol Spectrosc ; 135: 283-95, 2015 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-25078461

RESUMO

Comprehensive investigation of geometrical and electronic structure in ground as well as the first excited state of 3,5-Difluoroaniline (C6H5NF2) was carried out. The experimentally observed spectral data (FT-TR and FT-Raman) of the title compound was compared with the spectral data obtained by DFT/B3LYP method using 6-311++G(d,p) basis set. The molecular properties like dipole moment, polarizability, first static hyperpolarizability, molecular electrostatic potential surface (MEPs), and contour map were calculated to get a better insight of the properties of the title molecule. Natural bond orbital (NBO) analysis was applied to study stability of the molecule arising from charge delocalization. UV-Vis spectrum of the title compound was also recorded and the electronic properties, such as Frontier orbitals and band gap energies were measured by TD-DFT approach. Total and partial density of state (TDOS and PDOS) and also overlap population density of state (OPDOS) diagrams analysis were presented. Global and local reactivity descriptors were computed to predict reactivity and reactive sites on the molecule. (1)H and (13)C NMR spectra by using gauge including atomic orbital (GIAO) method of studied compound were compared with experimental data obtained. Moreover, the thermodynamic properties were evaluated.


Assuntos
Compostos de Anilina/química , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Teoria Quântica , Análise Espectral Raman , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Elétrons , Conformação Molecular , Espectroscopia de Prótons por Ressonância Magnética , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Eletricidade Estática , Termodinâmica , Vibração
4.
Spectrochim Acta A Mol Biomol Spectrosc ; 133: 165-77, 2014 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-24934975

RESUMO

FT-IR and FT-Raman spectra of anethole (1-Methoxy-4-(1-propenyl)benzene), a flavoring agent of commercial value, have been recorded in the regions 4000-400 and 4000-100cm(-1) respectively. The structure of the title molecule has been optimized and the structural parameters have been calculated by DFT/B3LYP method with 6-311++G(d,p) basis set. The fundamental vibrational wavenumbers as well as their intensities were calculated and a good agreement between observed and scaled calculated wavenumbers has been achieved. UV-Vis spectrum of the title compound was recorded in the region 200-500nm and the electronic properties such as HOMO and LUMO energies and associated energy gap were calculated by Time dependent-density functional theory (TD-DFT) approach. Nonlinear optical (NLO) study divulges the nonlinear properties of the molecule. Stability of the title molecule arising from hyper-conjugative interactions and charge delocalization has been investigated using natural bond orbital (NBO) analysis. The theoretical results were found to be in coherence with the measured experimental data.


Assuntos
Anisóis/química , Aromatizantes/química , Derivados de Alilbenzenos , Modelos Moleculares , Teoria Quântica , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman
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