11 research outputs found
Peroxydisulfate activation by [RuII(tpy)(pic)(H2O)]+. Kinetic, mechanistic and anti-microbial activity studies
The oxidation of [RuII(tpy)(pic)H2O]+ (tpy = 2,2âČ,6âČ,2âČâČ-terpyridine; picâ = picolinate) by peroxidisulfate
(S2O8
2â) as precursor oxidant has been investigated kinetically by UV-VIS, IR and EPR spectroscopy.
The overall oxidation of Ru(II)- to Ru(IV)-species takes place in a consecutive manner involving oxidation
of [RuII(tpy)( pic)H2O]+ to [RuIII(tpy)( pic)(OH)]+, and its further oxidation of to the ultimate product
[RuIV(tpy)( pic)(O)]+ complex. The time course of the reaction was followed as a function of [S2O8
2â],
ionic strength (I) and temperature. Kinetic data and activation parameters are interpreted in terms of an
outer-sphere electron transfer mechanism. Anti-microbial activity of RuII(tpy)(pic)H2O]+ complex by
inhibiting the growth of Escherichia coli DH5α in presence of peroxydisulfate has been explored, and
the results of the biological studies have been discussed in terms of the [RuIV(tpy)( pic)(O)]+ mediated
cleavage of chromosomal DNA of the bacteria
Tandem detection of sub-nano molar level CN and Hg2+ in aqueous medium by suitable molecular sensor: a viable solution for detection of CN and development of RGB based sensory device
An inimitable urea-based multichannel chemosensor, DTPH [1,5-bis-(2,6-dichloro-4-(trifluoromethyl)phenyl)carbonohydrazide], was examined to be highly proficient to recognize CNâ based on the H-bonding interaction between sensor âNH moiety and CNâ in aqueous medium with explicit selectivity. In the absorption spectral titration of DTPH, a new peak at higher wavelength was emerged in titrimetric analytical studies of CNâ with the zero-order reaction kinetics affirming the substantial sensorâanalyte interaction. The isothermal titration calorimetry (ITC) experiment further affirmed that the sensing process was highly spontaneous with the Gibbs free energy of â26 Ă 104 cal/mol. The binding approach between DTPH and CNâ was also validated by more than a few experimental studies by means of several spectroscopic tools along with the theoretical calculations. A very low detection limit of the chemosensor toward CNâ (0.15 ppm) further instigated to design an RGB-based sensory device based on the colorimetric upshots of the chemosensor in order to develop a distinct perception regarding the presence of innocuous or precarious level of the CNâ in a contaminated solution. Moreover, the reversibility of the sensor in the presence of CNâ and Hg2+ originated a logic gate mimic ensemble. Additionally, the real-field along with the in vitro CNâ detection efficiency of the photostable DTPH was also accomplished by using various biological specimens
Hydrazine functionalized probes for chromogenic and fluorescent ratiometric sensing of pH and Fâ: experimental and DFT studies
Two novel hydrazine based sensors, BPPIH (N1,N3-bis(perfluorophenyl)isophthalohydrazide) and BPBIH (N1âČ,N3âČ-bis(perfluorobenzylidene)isophthalohydrazide), are presented here. BPPIH is found to be a highly sensitive pH sensor in the pH range 5.0 to 10.0 in a DMSOâwater solvent mixture with a pKa value of 9.22. Interesting optical responses have been observed for BPPIH in the above mentioned pH range. BPBIH on the other hand turns out to be a less effective pH sensor in the above mentioned pH range. The increase in fluorescence intensity at a lower pH for BPPIH was explained by using density functional theory. The ability of BPPIH to monitor the pH changes inside cancer cells is a useful application of the sensor as a functional material. In addition fluoride (Fâ) selectivity studies of these two chemosensors have been performed and show that between them, BPBIH shows greater selectivity towards Fâ. The interaction energy calculated from the DFT-D3 supports the experimental findings. The pH sensor (BPPIH) can be further interfaced with suitable circuitry interfaced with desired programming for ease of access and enhancement of practical applications
A novel ditopic chemosensor for cadmium and fluoride and its possible application as a pH sensor
A urea-based BPC [1,5-bis(perfluorophenyl)carbonohydrazide] molecule with four acidic NH protons has been synthesized by a facile synthetic process. The molecule was found to be a ditopic chemosensor for Cd2+ and Fâ ions. BPC was synthesized from low-cost starting materials, dinitrophenyl hydrazine and triphosgene. The hostâguest interactions between the ions (Cd2+ and Fâ) were not only confirmed by convenient spectroscopic techniques such as UV-Vis, PL, 1H-NMR, FT-IR, and cyclic voltammetry but also through modern DFT, the results of which were in good agreement with the experimental results. In vitro studies in human cancer cells (HeLa cells) were successfully performed with BPC and Cd2+ using fluorescence microscopy. The reversible UV-Vis response for BPC with Fâ, OHâ and H+ mimics multiple logic functions and can be used for several complex electronic circuits based on logic operations. The pH sensor (BPC) can be further interfaced with suitable circuitry interfaced with appropriate programming for ease of access and enhancement of its practical applications
Interaction of Ru<sup>III</sup>(EDTA) with cellular thiols and O<sub>2</sub>: biological implications thereof
<div><p>Reaction of [Ru<sup>III</sup>(EDTA)(CyS)]<sup>2â</sup> (edta<sup>4â</sup> = ethylenediaminetetraacetate; CySH = cysteine) with molecular oxygen (O<sub>2</sub>) has been studied as a function of pH (4.0â8.0) and cysteine concentration (0.2â2.0 mM) at room temperature (25 °C). Biological activities of the [Ru(EDTA)]/CySH/O<sub>2</sub> system pertaining to cleavage of supercoiled plasmid DNA to its nicked open circular form has been explored in this work. Results are discussed in regard to the reaction of the ruthenium(III)-complex with molecular oxygen) and a working mechanism is proposed for the biological activities of the ruthenium(III)-complex in the presence of O<sub>2</sub>.</p></div
Mining local process models and their correlations
\u3cp\u3eMining local patterns of process behavior is a vital tool for the analysis of event data that originates from flexible processes, which in general cannot be described by a single process model without overgeneralizing the allowed behavior. Several techniques for mining local patterns have been developed over the years, including Local Process Model (LPM) mining, episode mining, and the mining of frequent subtraces. These pattern mining techniques can be considered to be orthogonal, i.e., they provide different types of insights on the behavior observed in an event log. In this work, we demonstrate that the joint application of LPM mining and other patter mining techniques provides benefits over applying only one of them. First, we show how the output of a subtrace mining approach can be used to mine LPMs more efficiently. Secondly, we show how instances of LPMs can be correlated together to obtain larger LPMs, thus providing a more comprehensive overview of the overall process. We demonstrate both effects on a collection of real-life event logs.\u3c/p\u3
Notes for genera â Ascomycota
Knowledge of the relationships and thus the classification of fungi, has developed rapidly with increasingly widespread use of molecular techniques, over the past 10--15Â years, and continues to accelerate. Several genera have been found to be polyphyletic, and their generic concepts have subsequently been emended. New names have thus been introduced for species which are phylogenetically distinct from the type species of particular genera. The ending of the separate naming of morphs of the same species in 2011, has also caused changes in fungal generic names. In order to facilitate access to all important changes, it was desirable to compile these in a single document. The present article provides a list of generic names of Ascomycota (approximately 6500 accepted names published to the end of 2016), including those which are lichen-forming. Notes and summaries of the changes since the last edition of `Ainsworth Bisby's Dictionary of the Fungi' in 2008 are provided. The notes include the number of accepted species, classification, type species (with location of the type material), culture availability, life-styles, distribution, and selected publications that have appeared since 2008. This work is intended to provide the foundation for updating the ascomycete component of the ``Without prejudice list of generic names of Fungi'' published in 2013, which will be developed into a list of protected generic names. This will be subjected to the XIXth International Botanical Congress in Shenzhen in July 2017 agreeing to a modification in the rules relating to protected lists, and scrutiny by procedures determined by the Nomenclature Committee for Fungi (NCF). The previously invalidly published generic names Barriopsis, Collophora (as Collophorina), Cryomyces, Dematiopleospora, Heterospora (as Heterosporicola), Lithophila, Palmomyces (as Palmaria) and Saxomyces are validated, as are two previously invalid family names, Bartaliniaceae and Wiesneriomycetaceae. Four species of Lalaria, which were invalidly published are transferred to Taphrina and validated as new combinations. Catenomycopsis Tibell Constant. is reduced under Chaenothecopsis Vain., while Dichomera Cooke is reduced under Botryosphaeria Ces. De Not. (Art. 59)