scholarly journals Electron Densities & Cyclo-Voltammetry Studies of Mg, Al and Ca Calix-Aren Complexes

2020 ◽  
Vol 9 (3) ◽  
pp. 1320-1332
Keyword(s):  
Functional Groups ◽  
Metal Ion ◽  
Electrical Potential ◽  
Metal Extraction ◽  
Cavity Size ◽  
Electron Densities ◽  
Extraction Behavior ◽  
The Impact

Calixarenes are preferable for metal extraction because of the easy synthesis of a great number of derivatives, which allows comparing the impact of cavity size, conformation, functional groups, and other factors on the extraction behavior, and the flexibility to design a proper ligand to recognize a metal ion selectively. In this work, theoretically, it has been discussed on the specific Calix[n] and related cation in point of density and electrical potential via electron densities & cycle-voltammetry studies.

scholarly journals Comparison of Extraction Ability between a Mixture of Alamine 336/Aliquat 336 and D2EHPA and Ionic Liquid ALi-D2 from Weak Hydrochloric Acid Solution

Metals ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 1678
Author(s):  
Viet Nhan Hoa Nguyen ◽  
Minh Nhan Le ◽  
Man Seung Lee
Keyword(s):  
Ionic Liquid ◽  
Metal Ion ◽  
Extraction Efficiency ◽  
Ph Control ◽  
Metal Extraction ◽  
Aliquat 336 ◽  
Solution Ph ◽  
Remarkable Effect ◽  
Extraction Behavior ◽  
Alamine 336

The development of extraction systems to improve the extraction efficiency of metals using commercial extractants and ionic liquids is of importance. The extraction behavior of Co(II) between mixture of Alamine 336/Aliquat 336 and D2EHPA and synthesized ionic liquid ALi-D2 was compared in this work. Some factors, such as equilibrium pH, properties of the extractants, and concentration of components in the mixture had a remarkable effect on the extraction of Co(II). The interactions occurring in the mixtures as well as the change in solution pH were analyzed. Co(II) was completely extracted by ionic liquid when equilibrium pH was higher than 6.5, while it was difficult to extract Co(II) by employing the mixture of D2EHPA and Alamine 336/Aliquat 336. The formation of ionic liquid in the mixture of D2EHPA and Aliquat 336 was verified through FT-IR spectra. In addition, the competition extraction of hydrogen ion and Co(II) by ionic liquid ALi-D2 was explained. Among the three kinds of extractants, the ionic liquid showed the best extraction efficiency for Co(II) and pH control from weak acidic solutions. The present study provides valuable information on the extraction behavior of metal ion by the mixtures of commercial extractants, and thus can give some light on the development of metal extraction systems.

scholarly journals Synthesis and Biological Activity of Brassinosteroid Analogues with a Nitrogen-Containing Side Chain

2020 ◽  
Vol 22 (1) ◽  
pp. 155
Author(s):  
Mikhail V. Diachkov ◽  
Karoll Ferrer ◽  
Jana Oklestkova ◽  
Lucie Rarova ◽  
Vaclav Bazgier ◽  
...  
Keyword(s):  
Biological Activity ◽  
Functional Groups ◽  
Side Chain ◽  
Biotic And Abiotic Stresses ◽  
Short Side ◽  
Arabidopsis Root ◽  
Physiological Processes ◽  
Growth Promoting ◽  
The Impact ◽  
Brassinosteroid Analogues

Brassinosteroids are a class of plant hormones that regulate a broad range of physiological processes such as plant growth, development and immunity, including the suppression of biotic and abiotic stresses. In this paper, we report the synthesis of new brassinosteroid analogues with a nitrogen-containing side chain and their biological activity on Arabidopis thaliana. Based on molecular docking experiments, two groups of brassinosteroid analogues were prepared with short and long side chains in order to study the impact of side chain length on plants. The derivatives with a short side chain were prepared with amide, amine and ammonium functional groups. The derivatives with a long side chain were synthesized using amide and ammonium functional groups. A total of 25 new brassinosteroid analogues were prepared. All 25 compounds were tested in an Arabidopsis root sensitivity bioassay and cytotoxicity screening. The synthesized substances showed no significant inhibitory activity compared to natural 24-epibrassinolide. In contrast, in low concentration, several compounds (8a, 8b, 8e, 16e, 22a and 22e) showed interesting growth-promoting activity. The cytotoxicity assay showed no toxicity of the prepared compounds on cancer and normal cell lines.

scholarly journals Zinc limitation in Klebsiella pneumoniae profiled by quantitative proteomics influences transcriptional regulation and cation transporter-associated capsule production

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
A. Sukumaran ◽  
S. Pladwig ◽  
J. Geddes-McAlister
Keyword(s):  
Klebsiella Pneumoniae ◽  
Metal Ion ◽  
Ion Homeostasis ◽  
Cellular Protein ◽  
Pcr Analysis ◽  
Phenotypic Analysis ◽  
Metal Ion Homeostasis ◽  
Capsule Production ◽  
The Impact

Abstract Background Microbial organisms encounter a variety of environmental conditions, including changes to metal ion availability. Metal ions play an important role in many biological processes for growth and survival. As such, microbes alter their cellular protein levels and secretion patterns in adaptation to a changing environment. This study focuses on Klebsiella pneumoniae, an opportunistic bacterium responsible for nosocomial infections. By using K. pneumoniae, we aim to determine how a nutrient-limited environment (e.g., zinc depletion) modulates the cellular proteome and secretome of the bacterium. By testing virulence in vitro, we provide novel insight into bacterial responses to limited environments in the presence of the host. Results Analysis of intra- and extracellular changes identified 2380 proteins from the total cellular proteome (cell pellet) and 246 secreted proteins (supernatant). Specifically, HutC, a repressor of the histidine utilization operon, showed significantly increased abundance under zinc-replete conditions, which coincided with an expected reduction in expression of genes within the hut operon from our validating qRT-PCR analysis. Additionally, we characterized a putative cation transport regulator, ChaB that showed significantly higher abundance under zinc-replete vs. -limited conditions, suggesting a role in metal ion homeostasis. Phenotypic analysis of a chaB deletion strain demonstrated a reduction in capsule production, zinc-dependent growth and ion utilization, and reduced virulence when compared to the wild-type strain. Conclusions This is first study to comprehensively profile the impact of zinc availability on the proteome and secretome of K. pneumoniae and uncover a novel connection between zinc transport and capsule production in the bacterial system.

Biosorption of Cadmium onto Pseudomonas fluorescens: Application of Isotherm and Kinetic Models

2010 ◽  
Vol 171-172 ◽  
pp. 49-52 ◽  
Author(s):  
Chang Li Yu ◽  
Zhi Peng Lu ◽  
Fa Zhi Ge ◽  
Er Li Zhao
Keyword(s):  
Pseudomonas Fluorescens ◽  
Functional Groups ◽  
Metal Ion ◽  
Freundlich Isotherm ◽  
Industrial Effluents ◽  
Rate Equations ◽  
Isotherm Models ◽  
Maximum Adsorption Capacity ◽  
Kinetics Of Adsorption ◽  
Isotherm And Kinetic Models

The present study was undertaken to evaluate the feasibility of Pseudomonas fluorescens biomass for the removal of cadmium ions from aqueous solutions. Batch experiments were performed to study the adsorption of cadmium on pH, Pseudomonas fluorescens biomass adsorbent with respect to initial Cd(II) concentration, contact time and biomass dose. The experimental data were modeled by Langmuir and Freundlich isotherm models. Langmuir model resulted in the best fit of the adsorption data. The maximum adsorption capacity for Cd(II) was 66.25 mg/g (pH 5.0 and 5 g/L biomass dose). Kinetics of adsorption followed second-order rate equations. The FTIR results of Pseudomonas fluorescens biomass showed that biomass has different functional groups and these functional groups are able to react with metal ion in aqueous solution. The results of the present study suggest that Pseudomonas fluorescens biomass can be used beneficially in treating industrial effluents containing heavy metal ions.

Optical Metal Ion Sensor Based on Diffusion Followed by an Immobilizing Reaction. Quantitative Analysis by a Mesoporous Monolith Containing Functional Groups

2005 ◽  
Vol 77 (10) ◽  
pp. 3231-3237 ◽  
Author(s):  
D. Lynn Rodman ◽  
Hongjun Pan ◽  
Cheri W. Clavier ◽  
Xiaobing Feng ◽  
Zi-Ling Xue
Keyword(s):  
Quantitative Analysis ◽  
Functional Groups ◽  
Metal Ion ◽  
Ion Sensor

scholarly journals IMMOBILIZATION OF Saccharomycess cereviceae BIOMASS ON CHITOSAN AND ITS APPLICATION AS AN ADSORBENT FOR Pb(II) ION

2011 ◽  
Vol 11 (2) ◽  
pp. 174-179 ◽  
Author(s):  
Hasri Hasri ◽  
Mudasir Mudasir ◽  
Nurul Hidayat Aprilita ◽  
Roto Roto
Keyword(s):  
Optimum Condition ◽  
Functional Groups ◽  
Contact Time ◽  
Metal Ion ◽  
Mass Ratio ◽  
Adsorption Experiment ◽  
Ion Removal ◽  
Before And After ◽  
The Difference

An application of Saccharomycess cereviceae biomass immobilized on chitosan (SC-Chi adsorbent) for Pb(II) ion removal was demonstrated. Adsorption experiment was conducted at various mass ratio of Saccharomycess cereviceae biomass to chitosan, contact time, pH of solution and concentration of cation. Total Pb(II) metal ion adsorbed was calculated from the difference of the amount of metal ion before and after adsorption which was measured by AAS. The results showed that optimum condition for adsorption of Pb(II) ion by the SC-Chi was achieved using mass ratio of Saccharomycess cereviceae to chitosan of 50% (w/w), pH solution of 7, contact time of 60 min and concentration of 25 mgL-1. The hydroxyl (-OH) and amino (-NH2) functional groups are believed to be responsible for the adsorption of Pb(II) ion by the adsorbent.

scholarly journals Interactions, information and emergence: Exploring task allocation in ant colonies using network analysis

2021 ◽  
Author(s):  
Anshuman Swain ◽  
Sara D Williams ◽  
Louisa J Di Felice ◽  
Elizabeth A Hobson
Keyword(s):  
Network Analysis ◽  
Functional Groups ◽  
Task Allocation ◽  
Interaction Networks ◽  
Group Level ◽  
Ant Colonies ◽  
Individual Level ◽  
Network Measures ◽  
Interaction History ◽  
The Impact

In animal societies, individuals may take on different roles to fulfil their own needs and the needs of their groups. Ant colonies display high levels of organisational complexity, with ants fulfilling different roles at different timescales (what is known as task allocation). Factors affecting task allocation can be at the individual level (e.g., physiology), or at the group level (e.g., interaction histories). In this work, we focus on group level processes by exploring the impact of the history of interaction networks on task allocation and task switching using a previously published dataset (Mersch et al., 2013) tracking the behaviour of six Camponotus fellah colonies over 41 days. First, we investigated the architecture of interaction networks using node (individual) level network measures and their relation to the individual's task - foraging, cleaning or nursing - and whether or not the ant switched tasks. We then explored how noisy information propagation is among ants, as a function of the colony composition (how many ants are carrying out which tasks), through the information-theoretic metric of effective information. Our results show that interaction history affected task allocation, with ants more likely to switch to a task if they had interacted with other ants carrying out that task. The degree to which interaction history affected task allocation, as well as the noise in their interactions, depended on which groups of ants are interacting. Overall, we showed that colony cohesion is stable even as ant-level network measures vary more for ants when they switched functional groups; thus ant colonies maintain a high level of information flow as determined by network analysis and ant functional groups play different roles in maintaining colony cohesion.

scholarly journals The impact of functional groups of the surface of carbon materials on the efficiency of purification of extraction phosphoric acid from fluorine compounds

2019 ◽  
Vol 2 ◽  
pp. 11-18
Author(s):  
Smirnov N.N. ◽  
Konoval A.V. ◽  
Smirnova D.N. ◽  
Kochetkov S.P.
Keyword(s):  
Phosphoric Acid ◽  
Functional Groups ◽  
Carbon Materials ◽  
Raw Materials ◽  
Carbon Adsorbents ◽  
Joint Stock Company ◽  
Stock Company ◽  
Fluorine Compounds ◽  
The Impact ◽  
Extraction Phosphoric Acid

The environmental problems of the production of extraction phosphoric acid and the effect of fluorine on the human body are discussed in the article. The creation of the industry of phosphoric fertilizers on the basis of processing of fluorine-containing phosphate raw materials and fluorine-containing compounds, the development of their application require the study of environmental consequences arising from this, because fluorine is characterized by high mobility in the biological cycle of metabolism. For the purification of phosphoric acid from fluorine was used carbon adsorbents such as active charcoal brand BAU, natural graphite deposits Kyshtymsky, P514 soot, charcoal. Experiments on the purification was carried out on non-evaporated half-hydrated extraction phosphoric acid which was produced by joint stock company «Apatit» in Cherepovets city in Russia. The following analyses were carried out: IR-Fourier spectrometry, research of acid–base properties of carbon materials by potentiometric titration, potentiometric method of fluorine determination in extraction phosphoric acid. It is mentioned that the carbon black P514 is the most efficient adsorbent for purification of extraction phosphoric acid. The total number of functional groups on its surface is 0.62 mmol/g, the degree of purification from fluorine compounds is 94.8%.

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