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1.
Environ Monit Assess ; 196(3): 317, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38418672

RESUMO

Asian openbill stork (Anastomus oscitans) colonies and also the numbers were enormous before some decades in some villages beside Keleghai River bank. However, there has been a significant decline in both the colonies and their populations. This present study investigates the rapid decline in the number of breeding colonies and birds, exploring the reasons behind this phenomenon. To address these inquiries, the study collects perceptions from various stakeholders through extensive field observations and interviews. Expeditions are conducted to comprehend the prevailing situation and associated circumstances. Qualitative observations reveal that human intervention, both direct and indirect, is limiting the development of stork colonies. Data analysis indicates that 37.5% of respondents attribute the contraction of bird colonies to changes in land use, while 26.3% point to the extermination of larger trees along the colony periphery. Additionally, 18.05% of opinions implicate the heavy use of pesticides and fertilizers in the wetland, 6.94% cite local climate change, and 11.11% cite other reasons. To validate the gathered information, the study employed temporal land use land cover (LULC) classification techniques. Random point pattern analysis from Google Image of 2023 is also utilized to reinforce the survey results. It enhances understanding of the spatio-temporal relationship. Subsequently, the study presents the correlation matrix to elucidate the relationship between stork colonies and contributing factors. It provides a clear insight into the underlying situations. Finally, a comparative analysis of the surveyed and spatial analysis information is conducted to detect and validate the perception of stakeholders. Based on these observations, the study formulates conservation measures for the bird habitat and their colonies in the study area.


Assuntos
Monitoramento Ambiental , Rios , Animais , Humanos , Melhoramento Vegetal , Aves , Índia , Conservação dos Recursos Naturais
2.
Dalton Trans ; 49(47): 17140-17142, 2020 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-33200152

RESUMO

The capture, storage, and utilization (CSU) of CO2 to produce methanol which can be used as a fuel, fuel additive, and precursor in organic synthesis is an area of fascinating research. This directly influences the reduction of the CO2 concentration by capturing CO2 from industrial and automobile emissions. The development of integrated CO2 capture and conversion to a fuel and fuel additive has garnered considerable attention as it eliminates costly processes to produce pure CO2. This contribution presents a summary of integrated CO2 capture and conversion to methanol (MeOH) using amine-assisted and alkali hydroxide-assisted one-pot systems. The superiority of the alkali hydroxide-based system to the amine-based system for the conversion to MeOH is systematically presented.

3.
Monatsh Chem ; 149(4): 783-790, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29681658

RESUMO

ABSTRACT: The preparation, structural characterization, luminescence, and catalytic activity of three palladium(II) complexes bearing imino phenoxide ligands are reported. The X-ray studies revealed that the complexes are mononuclear with palladium centres coordinated in a square-planar coordination environment. Two of the complexes are emissive in solution at room temperature. The catalytic activities towards the ring-opening polymerization of rac-lactide (rac-LA) were tested. Polymers with moderate molecular weights and relatively broad dispersity (Ð) were obtained. Kinetic studies revealed that the polymerization followed first-order kinetics.

4.
Monatsh Chem ; 147(11): 1883-1892, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27795584

RESUMO

ABSTRACT: Four new copper complexes based on bidentate imino phenoxide ligands were synthesized and characterized by IR, UV-Vis spectroscopy, ESI mass spectrometry, single crystal X-ray diffraction, and electrochemistry. The crystal structures revealed that the copper(II) atoms are surrounded by phenolate oxygen and imine nitrogen atoms of two ligands in a distorted square-planar geometry. The existence of ligand-centered, as well as Cu(II)-centered quasi-reversible and reversible redox reactions are observed in the cyclic voltammetry experiments of all the complexes. All complexes are able to catalyze the ring-opening polymerization of rac-lactide yielding polymers with moderate molecular weights and moderately broad molecular weight distributions.

5.
Dalton Trans ; 42(28): 10304-14, 2013 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-23736066

RESUMO

Imino phenoxide complexes of Nb and Ta show precise control towards the solvent free ring-opening polymerization of lactides (LA) and ε-caprolactone (CL). There is a close proximity between the observed number average molecular weight (M(n)) and theoretical molecular weight and the molecular weight distributions (MWDs) were found to be narrow. Analysis of low molecular weight oligomers of LA synthesized from these compounds revealed that the ligand is incorporated as one of the end terminal groups in the polymer chain. In addition, these complexes were realized to be precatalysts for the polymerization of ethylene.

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