Production of polymeric nanocomposites by nature-like method and study of their physical and chemical properties

At the NRC “Kurchatov Institute” – GOSNIIGENETIKA, NpCdS nanocrystals were obtained by microbial synthesis. They were stabilized with proteins, which composition is determined by the strain used for biosynthesis of nanoparticles. Biogenic nanoparticles were studied and described by size, shape, hydrodynamic diameter, ζ potential, luminescence level, and defined as quantum dots applying methods of electron microscopy, dynamic light scattering, and spectrofluorimetry. The influence of temperature, pressure and solvents on the stability of biogenic nanoparticles and the luminescence intensity was evaluated in collaboration with IREA (NRC “Kurchatov Institute”). The luminescence intensity of the aqueous suspension of NpCdS was determined depending on the range of nanoparticle concentrations. The possibility of introducing and identifying NpCdS in epoxy resin, polyimide, and polyvinyl alcohol was assessed. Polymer nanocomposites are used for optoelectronic, biomedical and agricultural applications.

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Formulation, Physical and Chemical Stability of Ocimum gratissimum L. Leaf Oil Nanoemulsion

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.901.117 ◽

2021 ◽

Vol 901 ◽

pp. 117-122

Author(s):

Netnapa Ontao ◽

Sirivan Athikomkulchai ◽

Sarin Tadtong ◽

Phuriwat Leesawat ◽

Chuda Chittasupho

Keyword(s):

Essential Oil ◽

Zeta Potential ◽

Chemical Stability ◽

Polydispersity Index ◽

Hydrodynamic Diameter ◽

Potential Value ◽

Yellow Color ◽

Leaf Oil ◽

The Stability ◽

Physical And Chemical

Ocimum gratissimum L. leaf oil exhibited many pharmacological properties. This study aimed to formulate and evaluate the physical and chemical stability of O.gratissimum leaf oil nanoemulsion. O.gratissimum leaf oil was extracted by hydrodistillation. The major component of the essential oil eugenol, was analyzed by UV-Vis spectrophotometry. Nanoemulsions of O.gratissimum leaf oil were formulated using polysorbate 80, hyaluronic acid, poloxamer 188, and deionized water by phase inversion composition method. The hydrodynamic diameter, polydispersity index, and zeta potential value of O.gratissimum leaf oil nanoemulsion was evaluated by a dynamic light scattering technique. The %remaining of eugenol in the nanoemulsion was analyzed by UV-Vis spectrophotometry. The essential oil extracted from of O. gratissimum leaf oil was a clear, pale yellow color. The %yield of the essential oil was 0.15 ± 0.03% v/w. The size of the nanoemulsion was less than 106 nm. The polydispersity index of the nanoemulsion was ranging from 0.303 - 0.586 and the zeta potential value of the nanoemulsion was closely to zero, depending on the formulation component. O. gratissimum leaf oil at concentrations ranging from 0.002 - 0.012% v/v contained 35 - 41% of eugenol. The size of nanoemulsion was significantly decreased after storage at 4 °C, while significantly increased upon storage at 45 °C. The size of nanoemulsion stored at 30 °C did not significantly change. The %remaining of eugenol in the nanoemulsion was more than 90% after storage at 4 °C and 30 °C for 28 days. The percentage of eugenol remaining in the nanoemulsion stored at 45 °C was more than 85 - 90%, suggesting that the temperature affected the stability of eugenol in the nanoemulsion.

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Synthesis and Kinetic Investigations for the Isomerization Process of 2–Hydroxy Chalcone Derivatives

Journal of the chemical society of pakistan ◽

10.52568/000824/jcsp/41.06.2019 ◽

2019 ◽

Vol 41 (6) ◽

pp. 1046-1046

Author(s):

Omar A Shareef Omar A Shareef ◽

Said A Said and Ali Y Abdulrazaq Said A Said and Ali Y Abdulrazaq

Keyword(s):

Biological Activities ◽

Chemical Properties ◽

Physical And Chemical Properties ◽

Pseudo First Order Reaction ◽

First Order ◽

Steric Factors ◽

Kinetic Investigations ◽

The Stability ◽

Physical And Chemical ◽

And Chemical Properties

The wide biological activities of flavanones are mainly depends on their physical and chemical properties, thus a number of substituted 2-Hydroxy chalcones have been synthesized, and their isomerization to their corresponding flavanones was studied. In order to determine the rate constant, kinetic experiments were performed using HPLC technique in (9:1) (CH3CN:H2O) medium at different temperature (298-318) K. The obtained results were interpreted by four steps mechanism, which considered the existence of phenoxide ion as the key intermediate. This study performed with a pseudo first order ( reaction in which the rate for the studied compounds follow the sequence 5 andgt; 2 andgt; 1 andgt; 4 andgt; 3, the activation energy have the same sequence for these compounds .The effect of substituents on the rate showed that electronic and steric factors play reasonable role on the stability of the product .

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The Establishment of the 3rd National Reference Standard for Tachypleus Tridentatus Lysate

Journal of Applied Virology ◽

10.21092/jav.v6i3.90 ◽

2017 ◽

Vol 6 (3) ◽

pp. 50

Author(s):

Tong Cai ◽

Guolai Zhang ◽

Yusheng Pei ◽

Hua Gao

Keyword(s):

Chemical Properties ◽

Physical And Chemical Properties ◽

Reference Standard ◽

Tachypleus Tridentatus ◽

National Reference ◽

The Stability ◽

Physical And Chemical ◽

And Chemical Properties

Objective To establish the 3rd national reference standard for Tachypleus Tridentatus Lysate Reagent. Method and Results The candidates of reference standard were studied for the physical and chemical properties, and the stability. To determined its sensitivity by collaboration calibration. Conclusions The sensitivity of the 3rd national reference standard for TAL is 0.06EU / ml, lot number is 150603-201003.

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Effects of pyrolysis parameters on the yield and properties of biochar from pelletized sunflower husk

E3S Web of Conferences ◽

10.1051/e3sconf/20184400197 ◽

2018 ◽

Vol 44 ◽

pp. 00197 ◽

Cited By ~ 1

Author(s):

Katarzyna Wystalska ◽

Krystyna Malińska ◽

Renata Włodarczyk ◽

Olga Chajczyk

Keyword(s):

Food Processing ◽

Chemical Properties ◽

Total Carbon ◽

Physical And Chemical Properties ◽

Wide Range ◽

Agricultural Applications ◽

Agriculture And Food ◽

Pyrolysis Of Biomass ◽

Physical And Chemical ◽

And Chemical Properties

Pyrolysis of biomass residues from agriculture and food processing industry allows production of biochars with diverse physical and chemical properties for a wide range of applications in agriculture and environmental protection. Biochars produced from pelletized sunflower husks through slow pyrolysis in the range of temperatures (480–580°C) showed total carbon of 70.53%–81.96%, total nitrogen of 1.2%, alkaline pH (9.37–10.32), low surface area (0.93–2.91 m2 g-1) and porosity of 13.23–15.43%. Higher pyrolysis temperatures resulted in lower biochar yields. With the increase in temperature the content of organic matter, nitrogen, Ca and Mg decreased whereas the increase in temperature resulted in higher contents of total carbon and phosphorus. Produced biochars showed potential for agricultural applications.

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Salting-out and salting-in experiments with lignosulfonates (LSs)

Holzforschung ◽

10.1515/hf-2012-0163 ◽

2013 ◽

Vol 67 (5) ◽

pp. 549-557 ◽

Cited By ~ 12

Author(s):

Bernt O. Myrvold

Keyword(s):

Chemical Properties ◽

Physical And Chemical Properties ◽

Salting Out ◽

Practical Applications ◽

Common Ion ◽

The Common ◽

Common Ion Effect ◽

The Stability ◽

Physical And Chemical ◽

And Chemical Properties

Abstract The solubility of lignosulfonates (LSs) in water is strongly dependent on other ions present in the water phase. The differences in the solubility might strongly influence the measurements of the physical and chemical properties of the LS molecules. A reduced solubility of the LS might also affect its utility in many practical applications. The understanding of the interaction between LSs and various salts is important for both practical and theoretical reasons. Therefore, the effect of salt concentrations on the LS has been investigated for 41 different salts with 14 different cations and 16 different anions. The observations cannot be explained by the common ion effect or the screening effects. On the contrary, it was found that the stability of LS solutions follows the Hofmeister series, with the exception of those ions that will chemically interact with the LS molecule. Moreover, the positions of phosphate (HPO42-) and sulfate (SO42-) ions were reversed.

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The Fabrication and Progress of Core-Shell Composite Materials

Australian Journal of Chemistry ◽

10.1071/ch08420 ◽

2009 ◽

Vol 62 (12) ◽

pp. 1561 ◽

Cited By ~ 25

Author(s):

Shunsheng Cao ◽

Juanrong Chen ◽

Jie Hu

Keyword(s):

Materials Science ◽

Chemical Properties ◽

Core Shell ◽

Production Methods ◽

Potential Applicability ◽

Shell Particles ◽

The Stability ◽

Physical And Chemical ◽

Shell Composite ◽

Organic Particle

Core-shell materials, in which a layer or multilayer of inorganic or organic material surrounds an inorganic or organic particle core, have been investigated both as a means to improve the stability and surface chemistry of the core particle and as a way of accessing unique physical and chemical properties that are not possible from one material alone. As a result, the fabrication of core-shell particles is attracting a great deal of interest because of their unique properties and potential applicability in catalysis, semiconductors, drug delivery, enzyme immobilization, molecular recognition, chemical sensing, etc. As evidenced by the literature described and discussed in this review, a basic understanding of the mechanism and recent progress in production methods have enabled the fabrication of core-shell particles with unique and tailored properties for various applications in materials science.

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COMPLEXATION OF APPLE PECTIN, MODIFIED TO PHARMACOPHORE, WITH THE CATIONS MANGANESE (II) IN AQUEOUS SOLUTIONS

chemistry of plant raw material ◽

10.14258/jcprm.2020015161 ◽

2020 ◽

pp. 25-32

Author(s):

Roza Khanifovna Mudarisova ◽

Alina Failovna Sagitova ◽

Ol'ga Sergeyevna Kukovinets

Keyword(s):

Metal Complexes ◽

Chemical Properties ◽

Thermodynamic Characteristics ◽

Standard Thermodynamic Characteristics ◽

Anthranilic Acids ◽

Drug Compound ◽

The Stability ◽

Physical And Chemical ◽

And Chemical Properties ◽

Polymer Ligand

Complex formation in systems containing manganese (II), natural pectin and/or pectin modified by organic pharmacophores (nicotine, salicylic, 5-aminosalicylic, anthranilic acids) was studied by spectral (UV-, IR-, NMR 13C spectroscopy), potentiometric and viscometric methods. Method isomolar series and the molar relationship defined by the molar composition and the range of stability of metal complexes: pectin + nicotinic acid > pectin + acid 5-aminosalicylic > pectin + anthranilic acid > pectin + salicylic acid > native pectin. It is shown that the stability constant of metal complexes is significantly influenced by the reaction temperature and the structure of the pharmacophore. The presence of an amino group in the structure of an aromatic molecule increases the stability of metal complexes by 1.5–2 orders of magnitude. The standard thermodynamic characteristics (∆Hº; ∆Gº; ∆Sº) are calculated, which indicate that the processes of complexation in all cases are enthalpy-entropy favorable (∆Hº<0, ∆Sº>0) and proceed spontaneously (∆Gº<0). The influence of the structure of the drug compound in the polymer ligand on a number of physical and chemical properties of metal complexes was revealed. The data of NMR 13C and IR-spectra allow us to conclude that not only carboxyl groups but also hydroxyl functions of polymer matrices participate in the coordination interaction of pectin and/or pharmacophore-containing pectin with manganese (II) cations.

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Micelle Encapsulation of Ferromagnetic Nanoparticles of Iron Carbide@Iron Oxide in Chitosan as Possible Nanomedicine Agent

Colloids and Interfaces ◽

10.3390/colloids4020022 ◽

2020 ◽

Vol 4 (2) ◽

pp. 22

Author(s):

Perla Yazmin Sauceda-Oloño ◽

Hector Cardenas-Sanchez ◽

Anya Isabel Argüelles-Pesqueira ◽

Cindy Gutierrez-Valenzuela ◽

Mario Enrique Alvarez-Ramos ◽

...

Keyword(s):

Oleic Acid ◽

Iron Oxide ◽

Iron Carbide ◽

Sodium Dodecylsulfate ◽

Chemical Properties ◽

Chitosan Solution ◽

Iron Pentacarbonyl ◽

Hydrodynamic Diameter ◽

Shell Nanoparticles ◽

Physical And Chemical

In this work, the synthesis and characterization of core/shell nanoparticles of iron carbide@iron oxide (Fe3C/γ-Fe2O3) encapsulated into micelles of sodium dodecylsulfate and oleic acid and stabilized with chitosan was developed. The materials were sonosynthesized at low intensities using standard ultrasonic baths with iron pentacarbonyl (Fe(CO)5) and oleic acid as iron source and hydrophobic stabilizer, respectively; obtaining nanoparticles with a hydrodynamic diameter of 19.71 nm and polydispersive index (PDI) of 0.13. The iron carbide@iron oxide nanoparticles (ICIONPs) in oleic acid were used as the organic phase during the self-assemble of nanoemulsion with sodium dodecylsulfate in water to obtain the metastable micelles. The final step involved the stabilization of the micelles using low molecular weight chitosan solution at 2% in acetic acid by ultrasonication bath. The nanosystem showed a hydrodynamic diameter of 185.30 nm, a PDI of 0.15 with a superficial charge ζ of 36.70 mV. Due to the magnetic, physical and chemical properties previously measured of the ICIONPs, it is believed that this type of nanoparticles can be used as a possible nanomedicine agent.

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DEVELOPMENT OF EFFERVESCENT GRANULE OF CORN MILK, SUPPLEMENTED WITH PROBIOTICS LACTOBACILLUS STRAIN SHIROTA

International Journal of Applied Pharmaceutics ◽

10.22159/ijap.2018v10i5.27459 ◽

2018 ◽

Vol 10 (5) ◽

pp. 71

Author(s):

Reni Hiola ◽

Robert Tungadi

Keyword(s):

Citric Acid ◽

Tartaric Acid ◽

Milk Powder ◽

Chemical Properties ◽

Lactobacillus Strain ◽

Dissolution Time ◽

Wet Granulation ◽

Nutrient Contents ◽

The Stability ◽

Physical And Chemical

Objective: One of the materials which can be formulated into probiotics drink is corn milk. It has nutrient contents such as vitamin A, B, C, minerals, and fibres. The objective of this study was to develop and evaluate the probiotic drink of corn milk which was formulated into an effervescent granule.Methods: The first step was carried out to make corn extract with the addition of Lactobacillus strain Shirota and incubated 24 h at 40 °C to gain corn milk. After that, corn milk was centrifuged to get filtrate and dried by oven 40 °C for 2 d to gain dry powder. Then corn milk powder was formulated into effervescent granule (3 formulas) using different ratio of acids. The method which used in making effervescent granule of corn milk was wet granulation. All formulas were done evaluations including physical and chemical properties of granule and hedonic test.Results: The results showed that formula 1 (only citric acid 23.84%) gave unsatisfactory results particularly on the evaluation tests such as LOD 9.64%, dissolution time 3.25 min, moisture content 10.67% and hedonic test which did not meet the requirements. Otherwise, formula 2 (only tartaric acid 23.84%) and formula 3 (citric acid 7.94% and tartaric acid 15.9% combination) showed satisfactory results for all evaluation tests of granules. Particularly formula 3 gave pH 5 on pH test which was the same as pH lactic acid for fermentation and LOD 4.34%, MC 4.53%, ρb 0.53 g/ml, ρt 0.62 g/ml and hedonic test around 80%.Conclusion: Formula 3 was the best formulation based on the evaluation and the stability of corn milk effervescent granule.

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The Effect of pH on Stability of an Isolation Barrier Made of Dolomite Post-Floatation Waste

Minerals ◽

10.3390/min11121384 ◽

2021 ◽

Vol 11 (12) ◽

pp. 1384

Author(s):

Jolanta Sobik-Szołtysek

Keyword(s):

Chemical Properties ◽

Filtration Coefficient ◽

Grain Composition ◽

Fine Grained ◽

Column Material ◽

Initial Ph ◽

Alternative Material ◽

Leaching Solution ◽

The Stability ◽

Physical And Chemical

Dolomite post-floatation waste has been proposed as an alternative material for the construction of separation barriers. The aim of this study was to determine the effect of the pH of leaching solutions on the stability of such barriers. The present research included the determination of selected physical and chemical properties of waste, i.e., density, grain composition, and filtration coefficient. Column tests of leaching by solutions of different pH values modeling varying environmental conditions were performed. Selected ions were determined in the eluates. Grain analyses were carried out for the column material after leaching to determine the changes in grain composition of dolomite due to washing with leaching solutions. The determined value of the filtration coefficient is 6.52 × 10−9 m∙s−1, which confirms the impermeability of the waste. The material is fine-grained, with a grain diameter of d ≤ 200 µm. During leaching, a decrease in the content of the analyzed ions and the diameter of grains and their movement down the barrier, resulting in its sealing, was observed. The central part of all columns showed more grains with a diameter of 7 μm, which is probably due to secondary precipitation of CaSO4. Irrespective of the initial pH of the leaching solution, the reaction of all eluates obtained was slightly alkaline (pH 7.52–8.20). Dolomite post-floatation waste has properties that ensure the tightness and durability of the separation barrier, which, combined with its ability to alkalize solutions and the sealing process, ensures its effectiveness.

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