Colloid Journal最新文献

{"title":"Development of Materials Based on Poly(lactic acid) and Copper(II) Sulfate Impregnated by the Crazing Method","authors":"S. D. Brovina,&nbsp;E. E. Mastalygina,&nbsp;E. S. Trofimchuk,&nbsp;A. A. Popov","doi":"10.1134/S1061933X23601178","DOIUrl":"10.1134/S1061933X23601178","url":null,"abstract":"<p>The common approach to creating antimicrobial polymer materials is the distribution of a bactericidal additive in a material by mixing the additive with a solution or a melt of the polymer. This work proposes the method introducing of copper(II) sulfate, which has antimicrobial properties, into a poly(lactic acid) film by forced impregnation of a salt solution via the crazing mechanism. CuSO₄ has been found to be uniformly distributed in the bulk of the polymer in the form of particles with sizes of about 100 nm. In the course of the structural modification, the surface of the polymer film becomes rougher and more hydrophobic. The water contact angle increases from 40° to 60°–65°. The incorporation of CuSO₄ does not affect the surface properties but has a reinforcing effect on the polymer matrix as is evident from tensile tests (strength and elongation at break increase by 2.5 and 1.4 times, respectively).</p>","PeriodicalId":521,"journal":{"name":"Colloid Journal","volume":"86 1","pages":"4 - 13"},"PeriodicalIF":1.4,"publicationDate":"2024-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140169647","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of the Structure of Water-in-Oil Microemulsions of Sodium Di-(2-ethylhexyl)phosphate and Sodium Dodecyl Sulfate on the Efficiency of Microemulsion Leaching of Copper","authors":"N. M. Murashova,&nbsp;A. S. Polyakova","doi":"10.1134/S1061933X2360104X","DOIUrl":"10.1134/S1061933X2360104X","url":null,"abstract":"<p>A relationship has been found between the structure of microemulsions based on sodium dodecyl sulfate (SDS) and sodium di-(2-ethylhexyl)phosphate (D2EHPNa) and the efficiency of microemulsion leaching of copper. The dependences of electrical conductivity on the volume fraction of water have been studied for microemulsions containing D2EHPNa or a mixture of SDS and butanol, decane, water, and di-(2-ethylhexyl)phosphoric acid as an extractant for copper extraction. A gradual passage from water-in-oil microemulsions with the predominance of isolated droplets to microemulsions with the predominance of dynamic clusters of droplets (percolated structure) takes place with the increase in the volume fraction of water. The conductivity percolation thresholds are approximately 0.18 and 0.20 for the microemulsions based on D2EHPNa and SDS, respectively. The temperature dependence of the logarithmic electrical conductivity is linear in a range of 20–80°C for the microemulsions with water volume fractions below (0.13 and 0.07, respectively) and above (0.30 and 0.23) the percolation threshold; in this temperature range the structure of the considered microemulsions remains unchanged. The experiments on microemulsion leaching performed with the use of a CuO-based model system at <i>T</i> = 80°C have shown that, for the microemulsions with the percolated structure (having water volume fractions of 0.30 for D2EHPNa microemulsions and 0.23 for SDS microemulsions), copper extraction is higher than that for the microemulsions with the predominance of isolated droplets (water volume fraction of 0.13 and 0.07, respectively).</p>","PeriodicalId":521,"journal":{"name":"Colloid Journal","volume":"86 1","pages":"98 - 108"},"PeriodicalIF":1.4,"publicationDate":"2024-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140169652","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Finite Element Model for the Interaction of Liquid Metals with Reactor Steel","authors":"O. A. Chikova,&nbsp;V. S. Wang,&nbsp;S. L. Li","doi":"10.1134/S1061933X23601154","DOIUrl":"10.1134/S1061933X23601154","url":null,"abstract":"<p>The article discusses a model of the interaction between a liquid−metal coolant (Pb, Pb55Bi(e)) and a heat exchanger material (316L steel) in an SVBR-type nuclear reactor cooling device for the case in which the effect of liquid-metal embrittlement cannot be ignored. It is assumed that a crack propagates due to the penetration of the liquid-metal coolant into intergrain boundaries. The free energy of a wetted surface is calculated using the mean-field theory within the formalism of finite element analysis. Tensile stress <i>S</i> (MPa) is determined for the propagation of a crack 50 µm long from a defect in the form of a 0.15-mm scratch on the surface of the heat exchanger. The calculation is carried out for an operation temperature range of 900–1100 K, when the melt wets the steel. The values of <span>(S = 253{kern 1pt} -{kern 1pt} 358)</span> and <span>(210{kern 1pt} -{kern 1pt} 369,,~{text{MPa}})</span> have been obtained for the interaction of Pb55Bi melts and Pb with 316L steel, respectively. The calculation results mean that a heat exchanger with surface defects can be damaged due to the effect of liquid-metal embrittlement.</p>","PeriodicalId":521,"journal":{"name":"Colloid Journal","volume":"86 1","pages":"130 - 137"},"PeriodicalIF":1.4,"publicationDate":"2024-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140169865","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modification of Synthetic Valleriite Surface with Gold Nanoparticles: The Roles of Specific Adsorption and Zeta Potential","authors":"A. A. Karacharov,&nbsp;M. N. Likhatski,&nbsp;R. V. Borisov,&nbsp;E. V. Tomashevich,&nbsp;S. A. Vorobyev,&nbsp;S. M. Zharkov","doi":"10.1134/S1061933X23601075","DOIUrl":"10.1134/S1061933X23601075","url":null,"abstract":"<p>Layered two-dimensional materials, whose properties dramatically differ from their bulk precursors, are of great theoretical and applied importance. Recently, a layered 2D material, an analog of a natural mineral, valleriite, in which quasi-monoatomic Cu−Fe−S sheets alternate with brucite-like ones, has been prepared using a simple hydrothermal synthesis procedure. The features of the electronic structure of these materials make it possible to propose them as new materials for a wide field of applications such as (electro)photocatalysis, high-capacity batteries, etc. In this work, nanocomposite materials have been prepared via immobilization of gold nanoparticles (AuNPs) from citrate hydrosols on the surface of the synthesized valleriites having different compositions of hydroxide layers, which control the surface charge density. According to X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), energy-dispersive X-ray microanalysis (EDX), and selected area electron diffraction (SAED) data, AuNPs are immobilized on valleriite nanoflakes, which have lateral sizes of 150–200 nm and thicknesses of several tens of nanometers, as isolated metal nanoparticles with an average diameter of 11 nm. A small amount of aggregates indicates a high affinity of AuNPs for the valleriite surface. The amounts of immobilized gold are the same on all studied valleriites (~0.2%). This finding may be related to the simultaneous sorption of free citrate ions from the AuNP hydrosols, with these ions, according to zeta potential measurements, charging the surfaces of all studied valleriite samples to nearly the same negative value of –40 mV. According to the XPS data, the AuNPs immobilization markedly decreases the magnesium and oxygen contents on the surfaces of the synthesized valleriites due to the partial degradation/dissolution of the brucite layer. In addition, the amount of Fe³⁺ ions bound to OH groups decreases with a simultaneous increase in the fraction of Fe³⁺–O species. The TEM data have confirmed the preservation of the layered structure of valleriites after the immobilization of AuNPs.</p>","PeriodicalId":521,"journal":{"name":"Colloid Journal","volume":"86 1","pages":"40 - 51"},"PeriodicalIF":1.4,"publicationDate":"2024-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140169648","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"On the Problem of Stability of Small Objects by the Example of Molecular Dynamics Models of Metal Nanoparticles and Nanosystems","authors":"V. M. Samsonov,&nbsp;N. Yu. Sdobnyakov,&nbsp;A. Yu. Kolosov,&nbsp;S. S. Bogdanov,&nbsp;I. V. Talyzin,&nbsp;S. A. Vasilyev,&nbsp;K. G. Savina,&nbsp;V. V. Puytov,&nbsp;A. N. Bazulev","doi":"10.1134/S1061933X23601191","DOIUrl":"10.1134/S1061933X23601191","url":null,"abstract":"<p>After briefly discussing the problem of stability/instability of dispersed systems in colloid chemistry, including ideas and concepts dating back to P.A. Rehbinder, the following classification has been proposed for instabilities of individual (free) nanoparticles: (1) instability with respect to the spontaneous disintegration into individual molecules (atoms) or smaller nanoclusters; (2) instability of shape; (3) instability of the integral structure of nanoparticles; (4) instability of the mesoscopic structure; (5) instability of physicochemical characteristics of nanoparticles; and (6) instability with respect to an external environment, including chemical instability, e.g., instability to oxidation. The problems concerning the stability of isomers of metal nanoclusters and of bimetallic core-shell nanostructures are considered as examples. The theoretical concepts of stability and instability have been illustrated by our molecular dynamics data on isomers of Au nanoclusters and mutually inverse (alternative) bimetallic Co@Au and Au@Co core-shell nanostructures, where the first element (before symbol @) corresponds to the central region (core) of a particle, while the second one refers to its shell.</p>","PeriodicalId":521,"journal":{"name":"Colloid Journal","volume":"86 1","pages":"109 - 119"},"PeriodicalIF":1.4,"publicationDate":"2024-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140169763","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Influence of the Structure of Sulfonic Polyelectrolyte Matrices on the Adsorption of Cu2+ Ions","authors":"S. G. Laishevkina,&nbsp;O. D. Iakobson,&nbsp;E. M. Ivan’kova,&nbsp;B. M. Shabsel’s,&nbsp;N. N. Shevchenko","doi":"10.1134/S1061933X23600999","DOIUrl":"10.1134/S1061933X23600999","url":null,"abstract":"<p>Porous hydrophilic polyelectrolyte matrices have been obtained by reverse suspension copolymerization of <i>p</i>-styrenesulfonate with <i>N</i>,<i>N</i>'-methylenebisacrylamide, as well as by cryotropic gelation of sulfonic acrylates (3-sulfopropyl methacrylate and sulfobetaine methacrylate). It has been shown that the concentration of sulfonate groups in the obtained polyelectrolytes is 2–3 mmol/g. The morphology and structure of the surface layer of the polyelectrolyte matrices have been studied by scanning electron microscopy and FTIR spectroscopy, while the specific surface area and pore size distribution have been investigated by the BET method. Adsorption of Cu²⁺ ions has been studied spectrophotometrically. It has been found that polyelectrolyte matrices containing aromatic sulfonate groups have the maximum sorption capacity.</p>","PeriodicalId":521,"journal":{"name":"Colloid Journal","volume":"86 1","pages":"86 - 97"},"PeriodicalIF":1.4,"publicationDate":"2024-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140169641","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Colloidal Properties of Sophora Japanese Fruit Dispersion","authors":"P. A. Vasileva,&nbsp;I. B. Dmitrieva","doi":"10.1134/S1061933X23601002","DOIUrl":"10.1134/S1061933X23601002","url":null,"abstract":"<p>Drug plant raw materials represent an important source of biologically active substances (BASs), which are used in pharmaceutical, cosmetic, food, and other industries. This paper presents the results of studying colloidal properties of crushed sophora Japanese fruits (hereinafter referred to as sophora) in order to improve the extraction of BASs. To achieve the goal, the following tasks have been set: the study of the ζ potential of sophora particles at different times of contact between the particles and an extractant and the pH values of the medium; determining the isoelectric point (IEP) of the sophora particles by electrophoresis; finding the point of zero charge (PZC) of sophora particles using potentiometric titration; and studying the influence of medium pH, sophora particle size, temperature, the presence of surfactants and ions, and the nature of an extractant on sophora swelling. The points of zero charge <span>({text{(p}}{{{text{H}}}_{{{text{PZC}}}}})</span>) of the aqueous dispersions of sophora and extracted flavonoids are 5.8 and 5.2, respectively, thus being close to the values <span>({text{p}}{{{text{H}}}_{{{text{IEP}}}}})</span>. The swelling of sophora particles is limited and accompanied by the gradual fracture of the plant cells. Adsorption equilibrium is achieved within 30 min. In an alkaline region and in the presence of alcohol, the swelling of the sophora particles decreases, while it increases at elevated temperature and in the presence of NaI ions.</p>","PeriodicalId":521,"journal":{"name":"Colloid Journal","volume":"86 1","pages":"23 - 32"},"PeriodicalIF":1.4,"publicationDate":"2024-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140169767","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Effects of Shear Parameters on the Stability of Emulsion Explosive Matrices","authors":"Jianmin Zhou,&nbsp;Yongsheng Jia,&nbsp;Yingkang Yao,&nbsp;Xianqi Xie,&nbsp;Mingsheng Zhao","doi":"10.1134/S1061933X23600872","DOIUrl":"10.1134/S1061933X23600872","url":null,"abstract":"<p>This work demonstrated the criterion of shear stability of emulsion explosive matrices (EEM), combined with rheology test, interfacial tension test, droplet size test and the crystallization test of emulsion explosive matrices. The shear stability of emulsion explosive matrices was defined as the characteristic refinement time of the droplet size decrease in emulsification process. The constitutive relationship between the characteristic refinement time and droplet size of inner phase droplets was proposed by theoretical analysis and experiments on the emulsification process of emulsion explosive matrices. By analyzing the relationship between rheological properties and characteristic refinement time of emulsion explosive matrices, the relationship model between Bingham coefficient and dimensionless coefficient was established to characterize the shear stability of emulsion explosive matrices. The effects of shear strength, shear time and shear shape on the stability of emulsion explosive matrices were studied. In addition, there exists a critical value to quantitatively characterize the shear stability of emulsion explosive matrices.</p>","PeriodicalId":521,"journal":{"name":"Colloid Journal","volume":"86 1","pages":"153 - 168"},"PeriodicalIF":1.4,"publicationDate":"2024-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139919504","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Preparation of Nanodiamond–Lysozyme–Miramistin Composite and Prospects of Its Application in Heart Valve Prosthetics","authors":"M. G. Chernysheva,&nbsp;G. A. Badun,&nbsp;A. G. Popov,&nbsp;I. S. Chashchin,&nbsp;N. M. Anuchina,&nbsp;A. V. Panchenko","doi":"10.1134/S1061933X23600987","DOIUrl":"10.1134/S1061933X23600987","url":null,"abstract":"<p>Creation of biocompatible coatings for xenogenic materials that can be used to manufacture prosthetic heart valves is an urgent and, unfortunately, still unsolved problem. It is necessary to obtain a biomaterial that would comply with the mechanical characteristics of a human valve and possess antimicrobial properties, which are of critical importance during the first postsurgical days. Biocompatible coatings can be used for this purpose, and it has turned out that detonation nanodiamonds are suitable for their preparation. The developed functional surface of nanodiamonds allows them to adsorb antibiotics; nanodiamonds are nontoxic and do not cause additional calcification. In this study, we have proposed to prepare a composite coating composed of nanodiamonds, lysozyme, and miramistin as broad-spectrum antimicrobial agents. The use of tritium-labeled nanodiamonds has made it possible to study the distribution of nanodiamond–lysozyme complexes after intravenous administration to mice and showed that the majority of the material remains at the place of injection. It has been shown that nanodiamond–lysozyme–miramistin composites exhibit strong antimicrobial activity, while the nanodiamond–miramistin complex shows no toxicity with respect to <i>Staphylococcus aureus</i>. Thus, the nanodiamond–lysozyme–miramistin composite can be used to create coatings for materials of prosthetic heart valves.</p>","PeriodicalId":521,"journal":{"name":"Colloid Journal","volume":"86 1","pages":"120 - 129"},"PeriodicalIF":1.4,"publicationDate":"2024-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139919642","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"New Polyfunctional Biamphiphilic Surfactants Based on Alkylmethylmorpholinium Cation and Dodecyl Sulfate Anion","authors":"D. M. Kuznetsov,&nbsp;D. A. Kuznetsova,&nbsp;F. G. Valeeva,&nbsp;L. Ya. Zakharova","doi":"10.1134/S1061933X23601051","DOIUrl":"10.1134/S1061933X23601051","url":null,"abstract":"<p>New biamphiphilic surfactants (BSs) have been synthesized based on alkylmethylmorpholinium cation and dodecyl sulfate anion (Mor-<i>n</i>(DS), <i>n</i> = 4, 6, 8, 10). The structure of the biamphiphiles has been characterized by IR spectroscopy, ¹H NMR spectroscopy, mass spectrometry, and elemental analysis. The aggregation behavior of the biamphiphiles in aqueous solutions has been assessed by tensiometry, conductometry, fluorescence spectroscopy (using a pyrene probe) and dynamic and electrophoretic light scattering. It has been shown that an increase in the hydrophobic tail length by two carbon atoms in an amphiphilic cation leads to an increase in the surface activity of the surfactant by ~5 units and a decrease in the aggregation threshold of the systems by 1.5–2 times. It has been established that the formation of aggregates with hydrodynamic diameters of 20–120 nm depending on the alkyl chain length of the alkylmethylmorpholinium cation and BS concentration. The zeta potential of the systems ranges from –25 to –100 mV and decreases with increasing biamphiphile concentration. Spectrophotometry has been employed to show a significant solubilization capacity of the biamphiphiles with respect to a hydrophobic dye Orange OT. The compounds obtained may be of interest for biomedical applications and other high-tech areas.</p>","PeriodicalId":521,"journal":{"name":"Colloid Journal","volume":"86 1","pages":"64 - 85"},"PeriodicalIF":1.4,"publicationDate":"2024-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139919498","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}