A phenol-formaldehyde polymeric network to generate organic aerogels: synthesis, physicochemical characteristics and potential applications

2018 ◽  
Vol 6 (3) ◽  
pp. 845-852 ◽  
Author(s):  
Halyna Zubyk ◽  
Olena Mykhailiv ◽  
Anthony N. Papathanassiou ◽  
Bogdan Sulikowski ◽  
Elzbieta Zambrzycka-Szelewa ◽  
...  
Keyword(s):  
Organic Solvent ◽  
Dye Removal ◽  
Phenol Formaldehyde ◽  
Physicochemical Characteristics ◽  
Water Sources ◽  
Polymeric Network ◽  
Potential Applications ◽  
Organic Aerogels

Two phenol-formaldehyde organic aerogels were prepared and applied for efficient Cu(ii) and Mn(ii) ion, organic solvent and dye removal from water sources.

Facile fractionation of bamboo hydrolysate and characterization of isolated lignin and lignin-carbohydrate complexes

Holzforschung ◽  
2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Xiaodi Wang ◽  
Yongchao Zhang ◽  
Luyao Wang ◽  
Xiaoju Wang ◽  
Qingxi Hou ◽  
...  
Keyword(s):  
Solvent Extraction ◽  
Organic Solvent ◽  
Extraction Process ◽  
Water Soluble ◽  
Organic Solvent Extraction ◽  
Glycoside Linkage ◽  
Potential Applications ◽  
Tremendous Amount ◽  
Main Components ◽  
Hemicellulosic Sugars

AbstractAn efficient separation technology for hydrolysates towards a full valorization of bamboo is still a tough challenge, especially regarding the lignin and lignin-carbohydrate complexes (LCCs). The present study aimed to develop a facile approach using organic solvent extraction for efficiently fractionating the main components of bamboo hydrolysates. The high-purity lignin with only a trace of carbohydrates was first obtained by precipitation of the bamboo hydrolysate. The water-soluble lignin (WSL) fraction was extracted in organic solvent through a three-stage organic solvent extraction process, and the hemicellulosic sugars with increased purity were also collected. Furthermore, a thorough characterization including various NMR techniques (31P, 13C, and 2D-HSQC), GPC, and GC-MS was conducted to the obtained lignin-rich-fractions. It was found that the WSL fraction contained abundant functional groups and tremendous amount of LCC structures. As compared to native LCC of bamboo, the WSL fraction exhibited more typical LCC linkages, i.e. phenyl glycoside linkage, which is the main type of chemical linkage between lignin and carbohydrate in both LCC samples. The results demonstrate that organic phase extraction is a highly efficient protocol for the fractionation of hydrolysate and the isolation of LCC-rich streams possessing great potential applications.

Chitosan-Stabilized Oil-in-Water Nanoemulsions

2022 ◽  
pp. 44-58
Author(s):  
Viktoria Milkova
Keyword(s):  
Physicochemical Characteristics ◽  
Biological Properties ◽  
Precise Control ◽  
Theoretical Approaches ◽  
Natural Polysaccharide ◽  
Oil In Water ◽  
Degree Of Acetylation ◽  
Key Factor ◽  
Potential Applications ◽  
The Stability

Chitosan is a natural polysaccharide and emulsifier that can ensure a significant emulsion stability at suitable pH, ionic strength, composition, concentration, or thermal processing. The evaluation of the electrokinetic properties is a key factor in investigation of the stability of the nanoemulsions with a view to their potential applications in bionanotechnology. Consequently, the precise control over the physicochemical characteristics of chitosan (degree of acetylation, DA and molecular weight, Mw) can provide a high stability and specific biological properties of the developed functional structures. The chapter is focused on the interpretation of the electrokinetic response from nanoemulsion stabilized by adsorption of chitosan (as a polyelectrolyte or uncharged polymer) by using appropriate theoretical approaches.

scholarly journals Cellulose Hydrogels for Rapid Dye Removal from Water

2020 ◽  
Author(s):  
Justin Harris ◽  
Anne McNeil
Keyword(s):  
Methylene Blue ◽  
Dye Removal ◽  
Cellulose Nanofibers ◽  
Water Sources ◽  
Water Remediation ◽  
Clean Water ◽  
Cationic Dye ◽  
Gel Formation ◽  
Potential Solution ◽  
Wood Pulps

<div><p>Clean water has become increasingly difficult to access due to the environmental discharge of pollutants. One potential solution is to develop materials that can efficiently remove pollutants from water sources through adsorption. Hydrogels have been explored for water remediation, but they often require long times to reach high levels of adsorption. To overcome this limitation, we developed a quick and locally formed hydrogel that adsorbs a common cationic dye during gel formation. Specifically, we demonstrate that hydrogels derived from cellulose – a renewable, non-toxic, and biodegradable resource – can efficiently remove methylene blue from water within seconds. We found that both sulfated cellulose nanofibers and sulfated wood pulps form localized gels when mixed with solutions containing a soluble, cationic cellulose derivative and the cationic dye. Overall, these localized hydrogels may be promising materials for remediating other water pollutants with further functionalization.</p></div>

scholarly journals Potential Applications in Relation to the Various Physicochemical Characteristics of Al-Hasa Oasis Clays in Saudi Arabia

2020 ◽  
Vol 10 (24) ◽  
pp. 9016
Author(s):  
Ibrahim A. Al-Hawas ◽  
Salah A. Hassan ◽  
Hany M. AbdelDayem
Keyword(s):  
Saudi Arabia ◽  
Adsorption Process ◽  
Physicochemical Characteristics ◽  
Methanol Conversion ◽  
The Other ◽  
Distribution Analysis ◽  
Removal Capacity ◽  
Other Hand ◽  
Potential Applications ◽  
Mineralogical Compositions

In this work, various physicochemical characteristics, e.g., surface properties and mineralogical compositions, of five clays collected from different sites in the Al-Hasa oasis in Saudi Arabia have been investigated. Analysis of the mineralogical compositions of the clays in the study by X-ray diffraction indicated the coexistence of palygorskite, montmorillonite, illite, kaolinite, chlorite, calcite and quartz in different percentages. Thermogravimetric analysis indicated that all studied clays exhibited dehydroxylation temperatures higher than 470 °C. On the other hand, pore size distribution analysis of clays from N2 adsorption indicated the presence of micro- and narrow mesopores (of 1.3–2.8 nm). Furthermore, the capability of the different clays for removal of Pb (II) from aqueous solution has been studied. The adsorption process was described through the Langmuir, Freundlich, Temkin and Dubinin–Radushkevich models. The Langmuir model was the most suitable compared to the other models in the case of palygorskite- and montmorillonite-rich clays. However, the Temkin model better represented the adsorption process of Pb (II) on calcite-rich clay. The clay sample with 61.0 wt% of palygorskite was found to be the most effective at removing Pb (II), with a maximum removal capacity of 74.07 mg/g at pH 6, with a contact time of 6 h and at 25 °C. Generally, the adsorption mechanism of lead over all the studied clays followed the pseudo-second-order kinetics. On the other hand, the catalytic activity of clays in the study has been tested in methanol conversion. The acidic clays, those containing high amounts of montmorillonite, showed higher selectivity to ethylene, viz., 78.9%, with a methanol conversion of 39.1% at 350 ° C and 0.1 MPa.

scholarly journals NANOPARTICLES: AN OVERVIEW OF THE PREPARATION METHODS FROM PREFORMED POLYMERS

2017 ◽  
Author(s):  
Barbara Stella ◽  
Alessandro Marengo ◽  
Silvia Arpicco
Keyword(s):  
Drug Delivery ◽  
Double Emulsion ◽  
Physicochemical Characteristics ◽  
Polymer Nanoparticles ◽  
Salting Out ◽  
Preparation Methods ◽  
Drug Degradation ◽  
Nanoparticle Preparation ◽  
Potential Applications ◽  
Organ Tissue

Polymer nanoparticles have many potential applications in biomedical field, since they can be used as drug delivery systems and/or for diagnostic purposes. The encapsulation into polymer nanoparticles may prevent drug degradation, control the rate and extent of release, and deliver a higher concentration of the active molecule to a desired organ/tissue. Nevertheless, the physicochemical characteristics of nanoparticles may greatly influence the activity of the encapsulated molecule. To obtain a suitable drug delivery system the choice of the nanoparticle preparation method is a crucial key. The selection of a specific technique is generally determined by the physicochemical characteristics of both polymer and drug, the delivery route, regulatory restrictions, and the desired physicochemical and morphological parameters of the nanoparticles. Two main strategies are employed for the preparation of polymer nanoparticles: the dispersion of preformed polymers and the polymerization of monomers. This review focuses on most commonly used methods that start from preformed polymers, and, in particular, on five techniques: nanoprecipitation, salting- out, emulsification diffusion, emulsification evaporation, and double emulsion solvent evaporation.

Capturing Cd(ii) and Pb(ii) from contaminated water sources by electro-deposition on hydrotalcite-like compounds

2016 ◽  
Vol 18 (3) ◽  
pp. 1838-1845 ◽  
Author(s):  
M. A. González ◽  
R. Trócoli ◽  
I. Pavlovic ◽  
C. Barriga ◽  
F. La Mantia
Keyword(s):  
Aqueous Solutions ◽  
Water Sources ◽  
Contaminated Water ◽  
Electro Deposition ◽  
Potential Applications ◽  
Toxic Pollutant ◽  
Electrochemical Removal

Two different hydrotalcite-like compounds were prepared and used as substrates for the electrochemical removal of extremely toxic pollutant cations, such as Cd(ii) and Pb(ii), from aqueous solutions, and their posterior recovery for further potential applications.

scholarly journals Nutritional Contribution of an Undervalued Ancestral Cucurbita, Study of Sicana sp. Endocarp, Epicarp and Seeds Composition

2021 ◽  
Vol 8 (1) ◽  
pp. 1
Author(s):  
Silvia Caballero ◽  
Eva Coronal ◽  
Anggie Burgos ◽  
Loida Galeano ◽  
Patricia Adelaida Piris Jara ◽  
...  
Keyword(s):  
Dietary Fiber ◽  
Beta Carotene ◽  
Physicochemical Characteristics ◽  
Dietary Guidelines ◽  
High Moisture Content ◽  
Fresh Weight ◽  
High Moisture ◽  
Peel Color ◽  
Potential Applications ◽  
Main Components

Native to South America, the Sicana sp. fruits, known in Paraguay as “kurugua”, belongs to the Cucurbit family and is almost extinct in the region. The aim of this study was to determine the physicochemical characteristics, composition and antioxidant activity of “kurugua” with reddish peel color. The determinations were made by official and regional standardized methodologies on fresh weight (FW). The pulp has an alkaline pH (7.41 ± 0.11), and its main components are carbohydrates (9.44 ± 0.45 g·100 g−1), followed by dietary fiber (1.74 ± 0, 04 g·100 g−1), as minor proteins (0.53 ± 0.05 g·100 g−1) and lipids (0.08 ± 0.01 g·100 g−1). On the evaluated antioxidants compounds, they were higher in peel than in pulp as; total phenols (279.2 ± 12.1, 55.7 ± 10.3 mg of GAE·100 g−1), Vitamin C (9.67 ± 0.09, 7.84 ± 1.71 mg·100 g−1) and beta-carotene (0.37 ± 0.03, 0.19 ± 0.01 mg·100 g−1), respectively. Fresh seeds have a high moisture content (38.8%), dietary fiber (40.2%) and lipids (11.74%), they mineral composition showed a high content of Mg and Ca and a high content of micronutrients such as Cu, Mn, Fe and Zn, which can represent a great contribution to the daily requirements of the diet. The red kurugua fruits are a natural source of nutritious and bioactive compounds beneficial to health, with multiple potential applications in foodstuff, which should be promoted in healthy dietary guidelines for the benefit of the populations.

scholarly journals Revisiting Jatropha curcas Monomeric Esterase: A Dienelactone Hydrolase Compatible with the Electrostatic Catapult Model

Biomolecules ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 1486
Author(s):  
Marcos Gustavo Araujo Schwarz ◽  
Deborah Antunes ◽  
Gabriela Coelho Brêda ◽  
Richard Hemmi Valente ◽  
Denise Maria Guimarães Freire
Keyword(s):  
Organic Solvent ◽  
Jatropha Curcas ◽  
Physicochemical Characteristics ◽  
Anion Exchange Chromatography ◽  
Catalytic Triad ◽  
Exchange Chromatography ◽  
Biodiesel Production ◽  
Two Dimensional Gel Electrophoresis ◽  
Dienelactone Hydrolase ◽  
Hydrolysis Activity

Jatropha curcas contains seeds with a high oil content, suitable for biodiesel production. After oil extraction, the remaining mass can be a rich source of enzymes. However, data from the literature describing physicochemical characteristics for a monomeric esterase from the J. curcas seed did not fit the electrostatic catapult model for esterases/lipases. We decided to reevaluate this J. curcas esterase and extend its characterization to check this apparent discrepancy and gain insights into the enzyme’s potential as a biocatalyst. After anion exchange chromatography and two-dimensional gel electrophoresis, we identified the enzyme as belonging to the dienelactone hydrolase family, characterized by a cysteine as the nucleophile in the catalytic triad. The enzyme displayed a basic optimum hydrolysis pH of 9.0 and an acidic pI range, in contrast to literature data, making it well in line with the electrostatic catapult model. Furthermore, the enzyme showed low hydrolysis activity in an organic solvent-containing medium (isopropanol, acetonitrile, and ethanol), which reverted when recovering in an aqueous reaction mixture. This enzyme can be a valuable tool for hydrolysis reactions of short-chain esters, useful for pharmaceutical intermediates synthesis, due to both its high hydrolytic rate in basic pH and its stability in an organic solvent.

Ionic Liquids—An Overview

2004 ◽  
Vol 57 (2) ◽  
pp. 113 ◽  
Author(s):  
Stewart A. Forsyth ◽  
Jennifer M. Pringle ◽  
Douglas R. MacFarlane
Keyword(s):  
Ionic Liquids ◽  
Organic Solvent ◽  
Physical Properties ◽  
Organic Solvent Media ◽  
Potential Applications ◽  
Media Research

Ionic liquids have become an increasingly popular class of solvent in the last decade as the potential applications of these materials become more diverse. Rather than being viewed simply as replacement for conventional organic solvent media, research into ionic liquids has progressed to the deliberate choice and design of these materials for reasons of improved rate, specificity, and yield. Design of ionic liquids centres on the development of novel cations and anions to impart the specific physical properties required for each application. Therefore, the materials being synthesized and studied are also becoming increasingly complex and diverse. Here we provide an overview of ionic liquids generally, and some of their current applications, as well as an introduction to some of the new cations and anions that have been developed for specific properties.

scholarly journals Assessment of Water Pollution in Tipparthy Revenue Sub-Division, Nalgonda (District), Andhra Pradesh, India

2010 ◽  
Vol 7 (s1) ◽  
pp. S587-S593
Author(s):  
Medikondu Kishore ◽  
Y. Hanumantharao
Keyword(s):  
Andhra Pradesh ◽  
Physicochemical Characteristics ◽  
Chemical Constituent ◽  
Water Sources ◽  
Total Hardness ◽  
Sodium Absorption ◽  
Hand Pump ◽  
Sodium Absorption Ratio ◽  
Almost All ◽  
Nalgonda District

A systematic study has been carried out to explore the physicochemical characteristics of drinking water sources of Tipparthy revenue sub-division, Nalgonda (District), Andhra Pradesh, India. Totally 49 water samples were collected from the different locations (22 villages) of the study area including bore well, open well and hand pump water and analyzed for pH, EC, TDS, turbidity, total hardness, fluoride, chloride, nitrate, nitrite, sulphate, phosphates, calcium, magnesium, sodium, potassium, Iron and dissolved oxygen. On an average, in almost all the samples, one or the other chemical constituent was beyond the permissible limits it was also concluded that water sources in the study area not fit for potability. Sodium absorption ratio (SAR) and water quality (WQI) studies indicate water available from all sources not fit for irrigation also. The study indicates the need for periodic monitoring of ground water in the study area.

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