Sign in to use this feature.

Years

Between: -

Subjects

remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline

Journals

Article Types

Countries / Regions

Search Results (25)

Search Parameters:
Keywords = colloids courses

Order results
Result details
Results per page
Select all
Export citation of selected articles as:
20 pages, 1246 KB  
Review
Fluid Therapy in Acute Pancreatitis—Current Knowledge and Future Perspectives
by Miłosz Caban, Hubert Zatorski and Ewa Małecka-Wojciesko
Pharmaceuticals 2025, 18(11), 1601; https://doi.org/10.3390/ph18111601 - 23 Oct 2025
Cited by 3 | Viewed by 8237
Abstract
Acute pancreatitis (AP) is one of the most frequent diseases requiring hospitalization in gastroenterology or intensive care unit departments. Its incidence and hospitalization rates have steadily increased over the last few years, contributing to high costs of medical care. This disease is associated [...] Read more.
Acute pancreatitis (AP) is one of the most frequent diseases requiring hospitalization in gastroenterology or intensive care unit departments. Its incidence and hospitalization rates have steadily increased over the last few years, contributing to high costs of medical care. This disease is associated with relevant mortality and morbidity rates. Fluid therapy in the first 48–72 h has an important role in the clinical course and complications; however, it has been raising numerous controversies recently. We present a review article summarizing the current knowledge about fluid therapy in AP. The demonstrated results are based on the most recent clinical studies published in the last five years. Data confirms that the therapy should be individualized along with the amount of fluids adapted to body mass, concomitant diseases, critical signs, and laboratory markers. A relevant issue in the context of fluid therapy of AP is fluid resuscitation that should be implemented in some patients upon hospital admission to maintain organ perfusion and substrate delivery. Ringer’s lactate should be preferred in the vast majority of AP cases over normal saline solution. Its use is associated with lowered risk of intensive care unit admission and local complications development, reduced hospital stay, and decreased mortality. Colloids, mainly hydroxyethyl starch, should not be recommended. Moderate-rate fluid infusion seems to be an advantage over high-rate infusion. Relying on presented results, fluid therapy has a key therapeutic role in AP management. Full article
(This article belongs to the Special Issue New and Emerging Treatment Strategies for Gastrointestinal Diseases)
Show Figures

Figure 1

25 pages, 5368 KB  
Article
Biogenic ZnO Nanoparticles Synthesized by B. licheniformis: A Selective Cytotoxicity Against NG-108 Glioblastoma Cells
by Alberto Bacilio Quispe Cohaila, Gabriela de Lourdes Fora Quispe, César Julio Cáceda Quiroz, Roxana Mamani Anccasi, Telmo Agustín Mejía García, Rocío María Tamayo Calderón, Francisco Gamarra Gómez and Elisban Juani Sacari Sacari
Nanomaterials 2025, 15(17), 1338; https://doi.org/10.3390/nano15171338 - 31 Aug 2025
Cited by 2 | Viewed by 1483
Abstract
Glioblastoma multiforme (GBM) remains the most aggressive primary brain tumor with median survival of 14.6 months, necessitating novel therapeutic approaches. Here, we report the biogenic synthesis of zinc oxide nanoparticles (ZnO NPs) using Bacillus licheniformis strain TT14s isolated from mining environments and demonstrate [...] Read more.
Glioblastoma multiforme (GBM) remains the most aggressive primary brain tumor with median survival of 14.6 months, necessitating novel therapeutic approaches. Here, we report the biogenic synthesis of zinc oxide nanoparticles (ZnO NPs) using Bacillus licheniformis strain TT14s isolated from mining environments and demonstrate their selective anti-glioma efficacy. ZnO NPs exhibited hexagonal wurtzite structure (crystallite size: 15.48 nm) with spherical morphology (19.37 ± 5.28 nm diameter) as confirmed by XRD, HRTEM, and comprehensive physicochemical characterization. Colloidal stability analysis revealed an isoelectric point at pH 7.46, ensuring optimal dispersion in biological media. Cytotoxicity evaluation revealed remarkable selectivity: at 100 μg/mL, ZnO NPs reduced NG-108 glioblastoma cell viability to 36.07 ± 1.89% within 1 h while maintaining 78.9 ± 0.94% viability in primary retinal cells. The selective cytotoxicity was attributed to the interplay of convergent mechanisms acting under dark conditions, including defect-mediated ROS generation supported by photoluminescence analysis revealing a characteristic oxygen vacancy emission at 550 nm, pH-dependent dissolution enhanced in the acidic tumor microenvironment, and preferential cellular uptake by rapidly proliferating cancer cells with compromised antioxidant defenses. Time-course analysis demonstrated concentration-dependent effects with therapeutic windows favoring normal cell preservation. The intrinsic cytotoxic activity under dark laboratory conditions eliminates the need for external activation, providing practical advantages for therapeutic applications. These findings establish ZnO NPs as promising candidates for targeted glioblastoma therapy, warranting further in vivo validation and mechanistic elucidation for clinical translation. Full article
Show Figures

Figure 1

14 pages, 1307 KB  
Article
Transient Gel Diffusiophoresis of a Spherical Colloidal Particle
by Hiroyuki Ohshima
Micromachines 2025, 16(3), 266; https://doi.org/10.3390/mi16030266 - 26 Feb 2025
Viewed by 1125
Abstract
A general theory is presented to analyze the time-dependent, transient diffusiophoresis of a charged spherical colloidal particle in an uncharged gel medium containing a symmetrical electrolyte when an electrolyte concentration gradient is suddenly applied. We derive the inverse Laplace transform of an approximate [...] Read more.
A general theory is presented to analyze the time-dependent, transient diffusiophoresis of a charged spherical colloidal particle in an uncharged gel medium containing a symmetrical electrolyte when an electrolyte concentration gradient is suddenly applied. We derive the inverse Laplace transform of an approximate expression for the relaxation function R(t), which describes the time-course of the ratio of the diffusiophoretic mobility of a weakly charged spherical colloidal particle, possessing a thin electrical double layer, to its steady-state diffusiophoretic mobility. The relaxation function depends on the mass density ratio of the particle to the electrolyte solution, the particle radius, the Brinkman screening length, and the kinematic viscosity. However, it does not depend on the type of electrolyte (e.g., KCl or NaCl), which affects only the steady-state gel diffusiophoretic mobility. It is also found that the expression for the relaxation function in transient gel diffusiophoresis of a weakly charged spherical colloidal particle with a thin electrical double layer takes the same form as that for its transient gel electrophoresis. Full article
Show Figures

Figure 1

13 pages, 1177 KB  
Article
Transient Diffusiophoresis of a Spherical Colloidal Particle
by Hiroyuki Ohshima
Colloids Interfaces 2025, 9(1), 7; https://doi.org/10.3390/colloids9010007 - 19 Jan 2025
Cited by 1 | Viewed by 2084
Abstract
A general theoretical approach is introduced to analyze the time-dependent, transient diffusiophoresis of a charged spherical colloidal particle in a symmetrical electrolyte solution when an electrolyte concentration gradient is suddenly applied. We derive a closed-form approximate expression for the relaxation function R( [...] Read more.
A general theoretical approach is introduced to analyze the time-dependent, transient diffusiophoresis of a charged spherical colloidal particle in a symmetrical electrolyte solution when an electrolyte concentration gradient is suddenly applied. We derive a closed-form approximate expression for the relaxation function R(t), which describes the time course of the diffusiophoretic mobility of a weakly charged spherical colloidal particle possessing a thin electrical double layer. The relaxation function depends on the mass density ratio of the particle to the electrolyte solution and the kinematic viscosity. However, it does not depend on the type of electrolyte (e.g., KCl or NaCl). It is also found that the expression for the relaxation function in transient diffusiophoresis of a weakly charged spherical colloidal particle with a thin electrical double layer takes the same form as that for its transient electrophoresis. Full article
(This article belongs to the Special Issue Biocolloids and Biointerfaces: 2nd Edition)
Show Figures

Figure 1

29 pages, 4818 KB  
Article
From Bin to Binder: Unleashing Waste Butter’s Potential as a Pioneering Bio-Modifier for Sustainable Asphalt Engineering
by Nader Nciri and Namho Kim
Sustainability 2024, 16(11), 4774; https://doi.org/10.3390/su16114774 - 4 Jun 2024
Cited by 3 | Viewed by 2381
Abstract
Exploring the interface of environmental sustainability and civil infrastructure development, this study introduces waste butter (WB), a byproduct of animal fat processing, as a novel bio-modifier in asphalt production. This approach not only recycles animal waste but also charts a course for sustainable [...] Read more.
Exploring the interface of environmental sustainability and civil infrastructure development, this study introduces waste butter (WB), a byproduct of animal fat processing, as a novel bio-modifier in asphalt production. This approach not only recycles animal waste but also charts a course for sustainable infrastructural development, contributing to a reduced environmental impact and promoting circular economy practices. The experiments incorporated varying WB concentrations (e.g., 3%, 6%, and 9% by weight of binder) into standard AP-5 asphalt, employing advanced analytical tools for comprehensive characterization. These included thin-layer chromatography–flame ionization detection (TLC-FID), Fourier-transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), and Differential Scanning Calorimetry (DSC). The critical properties of the asphalt blends, such as penetration, softening point, viscosity, ductility, rutting factor (Dynamic Shear Rheometer), and thermal susceptibility (Penetration Index, Penetration–Viscosity Number), were assessed. FT-IR analysis indicated negligible chemical alteration with WB addition, suggesting predominantly physical interactions. TLC-FID showed a decrease in aromatic and asphaltene components but an increase in resin content, highlighting the influence of WB’s fatty acids on the asphalt’s chemical balance. The colloidal instability index (IC) confirmed enhanced stability due to WB’s high resin concentration. Meanwhile, SEM analysis revealed microstructural improvements with WB, enhancing binder compatibility. TGA demonstrated that even a minimal 3 wt. % WB addition significantly improved thermal stability, while the DSC results pointed to improved low-temperature performance, reducing brittleness in cold conditions. Rheologically, WB incorporation resulted in increased penetration and ductility, balanced by decreased viscosity and softening point, thereby demonstrating its multi-faceted utility. Thermal susceptibility tests emphasized WB’s effectiveness in cold environments, with further evaluation needed at higher temperatures. The DSR findings necessitate careful WB calibration to meet Superpave rutting standards. In conclusion, this research positions waste butter as a superior, environmentally aligned bio-additive for asphalt blends, contributing significantly to eco-friendly civil engineering practices by repurposing animal-derived waste. Full article
Show Figures

Graphical abstract

10 pages, 1480 KB  
Article
Comparison of Left Ventricular End-Diastolic Volume Approximated from Mean Blood Pressure and Stroke Volume and End-Diastolic Volume Calculated from Left Ventricular-Aortic Coupling
by Takahiro Shiraishi, Yuka Matsuki, Yukiko Yamazaki and Kenji Shigemi
J. Clin. Med. 2024, 13(11), 3204; https://doi.org/10.3390/jcm13113204 - 29 May 2024
Cited by 1 | Viewed by 2186
Abstract
Objectives: The purpose of this study was to compare left ventricular end-diastolic volume (EDV), derived from left ventricular arterial coupling (Ees/Ea), and mean arterial blood pressure. Both of these methods of measuring EDV require some invasive procedure. However, the method of measuring EDV [...] Read more.
Objectives: The purpose of this study was to compare left ventricular end-diastolic volume (EDV), derived from left ventricular arterial coupling (Ees/Ea), and mean arterial blood pressure. Both of these methods of measuring EDV require some invasive procedure. However, the method of measuring EDV approximate is less invasive than the EDV coupling measuring method. This is because EDV approximate only requires arterial pressure waveform as an invasive procedure. Methods: This study included 14 patients with normal cardiac function who underwent general anesthesia. The point when blood pressure stabilized after the induction of anesthesia was taken as a baseline according to the study protocol. At the point when systolic arterial blood pressure fell 10% or more from the baseline blood pressure, 300 mL of colloid solution was administered over 15 min. EDV approximate and EDV coupling were calculated for each of the 14 patients at three points during the course of anesthetic. Each value was obtained by calculating a 5 min average. The timing of these three points was 5 min before, 5 min during, and 5 min after infusion loading. Results: The total number of comparable points was 42; 3 points were taken from each of the 14 participants. Both EDV approximate and EDV coupling increased through the infusion load testing. Scatter plots were prepared, and regression lines were calculated from the obtained values. A high correlation was shown between EDV approximate and EDV coupling (R2 = 0.96, p < 0.05). Conclusions: In patients with good cardiac function, EDV approximate can be substituted for EDV coupling, suggesting the possibility that EDV can be continuously and less invasively calculated under the situation of general anesthesia. Full article
(This article belongs to the Special Issue Anesthesia in General Surgery: Clinical Management and Challenges)
Show Figures

Figure 1

14 pages, 3638 KB  
Article
The Influence of Concentrations of Sensitizers and Activators on Luminescence Kinetics Parameters of Up-Conversion Nanocomplexes NaYF4:Yb3+/Tm3+
by Sergey Burikov, Ekaterina Filippova, Vera Proydakova, Sergey Kuznetsov, Valery Voronov, Natalia Tabachkova and Tatiana Dolenko
Photonics 2024, 11(3), 228; https://doi.org/10.3390/photonics11030228 - 29 Feb 2024
Cited by 6 | Viewed by 3247
Abstract
For colloids of NaYF4:Yb3+/Tm3+ nanoparticles in DMSO, by the method of time-resolved luminescence spectroscopy with nanosecond pulsed excitation at a wavelength of 975 nm, the photophysical processes that determine the course of kinetic curves have been revealed. It [...] Read more.
For colloids of NaYF4:Yb3+/Tm3+ nanoparticles in DMSO, by the method of time-resolved luminescence spectroscopy with nanosecond pulsed excitation at a wavelength of 975 nm, the photophysical processes that determine the course of kinetic curves have been revealed. It has been found that the luminescence rise time decreases with an increase in the concentration of activators and sensitizers due to the increase in the efficiency of energy transfer from sensitizers to activators. The cross-relaxation of the excited states of activators provides a decrease in the luminescence decay time with an increase in the concentration of activators and a constant concentration of the sensitizer. There is no correlation between the time of luminescence decay with the change in the concentration of sensitizers and the constant concentration of activators due to the competition of the processes of energy back transfer from activators to sensitizers and the “feeding” of activators by excitations coming from remote sensitizer ions. Full article
(This article belongs to the Special Issue Optical Spectroscopy and Applications)
Show Figures

Figure 1

23 pages, 6343 KB  
Article
Effects of Cooling Rate and Emulsifier Combination on the Colloidal Stability of Crystalline Dispersions Stabilized by Phospholipids and β-Lactoglobulin
by Jasmin Reiner, Charlotte Schüler, Volker Gaukel and Heike Petra Karbstein
Colloids Interfaces 2023, 7(2), 45; https://doi.org/10.3390/colloids7020045 - 5 Jun 2023
Cited by 6 | Viewed by 3780
Abstract
A lot of applications for (semi-)crystalline triacylglycerol (TAG)-in-water dispersions exist in the life science and pharmaceutical industries. Unfortunately, during storage, these dispersions are often prone to changes in particle size due to unforeseen crystallization and recrystallization events. This results in the alterations of [...] Read more.
A lot of applications for (semi-)crystalline triacylglycerol (TAG)-in-water dispersions exist in the life science and pharmaceutical industries. Unfortunately, during storage, these dispersions are often prone to changes in particle size due to unforeseen crystallization and recrystallization events. This results in the alterations of important product properties, such as viscosity and mouthfeel, or the premature release of encapsulated material. In this study, we investigated the effects and interplay of formulation, i.e., emulsifier combination, and processing parameters, i.e., cooling rate, on the colloidal stability of dispersed TAGs and aimed to improve their colloidal stability. We chose phospholipids (PLs) and β-lactoglobulin (β-lg) as the emulsifiers for our model systems, which are commonly applied in many food systems. When dispersions were characterized directly after cooling, we obtained smaller particles and narrower size distributions after fast cooling. Over the course of eleven weeks, the creaming behavior, particle size, melting behavior and polymorphism were characterized. The dispersions stabilized with solely β-lg exhibited a slight increase in particle size, whereas a decrease in size was found when PLs were added. Our results indicate that mass transport phenomena between TAG droplets and particles took place during storage. This migration of TAG molecules changed the composition and size distribution of the dispersed phase, especially at higher PL concentration (0.1 wt%). In our case, this could be prevented by using a lower concentration of PLs, i.e., 0.05 wt%. Full article
(This article belongs to the Special Issue Food Colloids: 2nd Edition)
Show Figures

Figure 1

21 pages, 3417 KB  
Article
Nitrogenous Bases in Relation to the Colloidal Silver Phase: Adsorption Kinetic, and Morphology Investigation
by Malgorzata Zienkiewicz-Strzalka and Magdalena Blachnio
Appl. Sci. 2023, 13(6), 3696; https://doi.org/10.3390/app13063696 - 14 Mar 2023
Cited by 6 | Viewed by 2435
Abstract
The interaction between inorganic nanoparticles and biological molecules is of great importance in the field of biosystems and nanomaterials. Here, we report the adsorption process of a heterocyclic organic compound (nitrogenous base) on a microporous carbon (C) in the presence of a colloidal [...] Read more.
The interaction between inorganic nanoparticles and biological molecules is of great importance in the field of biosystems and nanomaterials. Here, we report the adsorption process of a heterocyclic organic compound (nitrogenous base) on a microporous carbon (C) in the presence of a colloidal silver solution (AgNP solution) as an accompanying substance. Analysis of the potential colloid–biomolecule interaction as well as the subsequent phenomenon of changes in the morphology of the colloidal system in the presence of selected nucleotides was investigated. Adenosine nitrogenous base (Anb) was selected as a model molecule of the building block of DNA and RNA. The adsorption process of nucleotides from one- and two-component systems was monitored by cyclic UV-VIS measurements for obtaining time-dependent profiles and estimating the kinetic characteristics of uptake. We demonstrate the temperature-dependent course of the adsorption process with visible nucleotide-AgNP morphology determinants. The experimental adsorption kinetics were analyzed using selected theoretical models (intraparticle diffusion model, multiexponential equation, and many others). On the other hand, obtained Anb/C and Anb/AgNP/C composites were characterized by various techniques suitable for material surface and morphology characterization: high-resolution transmission electron microscopy (HR-TEM and TEM/EDX), N2 physisorption measurements, and thermal analysis (thermogravimetric analysis (TGA)/differential scanning calorimetry (DSC) experiments). Full article
(This article belongs to the Special Issue Nanostructured Materials: From Surface to Porous Solid)
Show Figures

Figure 1

16 pages, 4798 KB  
Article
Factors Regulating Fluid Restitution and Plasma Volume Reduction over the Course of Hemodialysis
by Jen-shih Lee and Lian-pin Lee
Toxins 2023, 15(1), 31; https://doi.org/10.3390/toxins15010031 - 31 Dec 2022
Cited by 5 | Viewed by 2768
Abstract
Over the course of hemodialysis, fluid and protein are restituted from the tissue compartment to the circulation compartment through the endothelia. Our previous model analysis on fluid and protein transport during hemodialysis is expanded to account for changes occurring in the tissue. The [...] Read more.
Over the course of hemodialysis, fluid and protein are restituted from the tissue compartment to the circulation compartment through the endothelia. Our previous model analysis on fluid and protein transport during hemodialysis is expanded to account for changes occurring in the tissue. The measured initial and end plasma protein concentration (PPC, Cp and Cp’) for six hemodialysis studies are analyzed by this expanded model. The computation results indicate that the total driving pressure to restitute fluid from the tissue to the circulation ranges from 5.4 to 20.3 mmHg. The analysis identifies that the increase in plasma colloidal osmotic pressure (COP) contributes 78 ± 6% of the total driving pressure, the decrease in microvascular blood pressure 32 ± 4%, the increase in the COP of interstitial fluid −6 ± 3%, and the decrease in interstitial fluid pressure −5 ± 2%. Let this ratio (Cp’ − Cp)/Cp’ be termed the PPC increment. The six HDs can be divided into three groups which are to have these PPC increments 25.7%, 14.5 ± 2.6(SD)% and 8.3%. It is calculated that their correspondent filtration coefficients are 0.43, 1.29 ± 0.28 and 5.93 mL/min/mmHg and the relative reductions in plasma volume (RRPV) −22.1%, −13.1 ± 6% and −9.4%. The large variations in PPC increments and RRPV show the filtration coefficient is a key factor to regulate the hemodialysis process. Full article
(This article belongs to the Special Issue Complications of Chronic Kidney Disease)
Show Figures

Graphical abstract

15 pages, 1909 KB  
Article
Laboratory Experiment on Emulsions: Study of the Effect of Osmotic Pressure on Double Emulsions Preparation
by María Matos, José Manuel Benito, Ángel Cambiella and Gemma Gutiérrez
Coatings 2022, 12(12), 1903; https://doi.org/10.3390/coatings12121903 - 6 Dec 2022
Cited by 2 | Viewed by 4017
Abstract
Double emulsions are ternary systems commonly used in several disciplines in areas such as food technology, applied chemistry, chemical engineering, materials science, pharmacology and environmental science. In several courses related to these areas, the implementation of laboratory experiment is required to strengthen the [...] Read more.
Double emulsions are ternary systems commonly used in several disciplines in areas such as food technology, applied chemistry, chemical engineering, materials science, pharmacology and environmental science. In several courses related to these areas, the implementation of laboratory experiment is required to strengthen the knowledge acquired by students during the theoretical lessons. However, it is difficult to find published practical experiments in this field. This work presents a four-hour hands-on laboratory experiment in which students can easily formulate and prepare water-in-oil-in-water double emulsions for vitamin B12 encapsulation. In this experiment, students can analyze the effect of the osmotic pressure produced by the addition of different NaCl concentrations in each aqueous phase, which could lead to the swelling and deswelling phenomena of the inner aqueous droplets and, therefore, affect the encapsulation efficiency of the formulated systems. The double emulsions are analyzed by the students in terms of size and encapsulation efficiency. Full article
Show Figures

Figure 1

13 pages, 1229 KB  
Article
Thyroid Surgery in Children: A 5-Year Retrospective Study at a Single Paediatric Surgical Center and Systematic Review
by Svetlana Bukarica, Jelena Antić, Ivana Fratrić, Dragan Kravarušić, Miloš Pajić and Radoica Jokić
Children 2022, 9(12), 1818; https://doi.org/10.3390/children9121818 - 25 Nov 2022
Cited by 8 | Viewed by 5288
Abstract
The aim of this study was to analyse and evaluate our 5-year experience in paediatric thyroid surgery, as well as the specificities of this kind of surgery in the literature. This retrospective study was based on 19 operations in 17 patients aged from [...] Read more.
The aim of this study was to analyse and evaluate our 5-year experience in paediatric thyroid surgery, as well as the specificities of this kind of surgery in the literature. This retrospective study was based on 19 operations in 17 patients aged from 5 to 17 years who were operated on due to thyroid pathology from 2017 until 2022. We presented data on surgical procedures and complications following surgery. Most of the patients were adolescent girls. The most common clinical presentations included enlarged thyroid gland, followed by thyroid nodules and hyperthyroidism. Eight total thyroidectomies, five left lobectomies, five right lobectomies, and three central neck dissections were performed. The most common histopathological diagnosis was hyperplastic diffuse colloid goitre, followed by papillary carcinoma, cystic nodule, follicular adenoma, Hashimoto thyroiditis and toxic adenoma. Postoperative course was uneventful, with four mild complications (one wound infection, one manifest hypocalcaemia, and two transitory recurrent laryngeal nerve paralysis). In our literature review, eighteen full-text articles were included and analysed. This study demonstrated that thyroid surgery in paediatric population is a safe and efficient procedure. Thyroid pathology in children significantly differs from that in the adults, and paediatric surgeons should be included into the team managing such cases. Full article
Show Figures

Figure 1

13 pages, 5454 KB  
Article
Ultrasonic Energy as an Agent to Aid Water Treatment in the Coagulation Process
by Longina Stępniak and Ewa Stańczyk-Mazanek
Energies 2022, 15(14), 5186; https://doi.org/10.3390/en15145186 - 18 Jul 2022
Cited by 5 | Viewed by 3256
Abstract
The aim of the study was to estimate the effectiveness of ultrasonic coagulation aiding. The effect of ultrasound exposure alone and associated systems (ultrasound exposure/coagulant) on the contamination of natural water was examined. The evaluation of the test results was based on changes [...] Read more.
The aim of the study was to estimate the effectiveness of ultrasonic coagulation aiding. The effect of ultrasound exposure alone and associated systems (ultrasound exposure/coagulant) on the contamination of natural water was examined. The evaluation of the test results was based on changes in indicators, such as TOC, color, turbidity, and electrokinetic potential. Three different coagulants were used in the tests of associated systems. The tests included basic processes related to volumetric coagulation, such as agitation, flocculation, and sedimentation. Sonication of water samples was carried out at a constant frequency of 22 kHz, variable vibration amplitude of 8–16 μm, and an exposure time of 1–5 min. The most efficient removal of organic contaminants from the water tested was achieved at a maximum amplitude of A = 16 μm, with effectiveness reaching 29% (TOC). In the tests of the associated systems, the effect of ultrasound exposure on the removal of water turbidity (an increase in the effectiveness of 25–35%) was generally greater than that on water color (8–21%). This relationship reflects the differentiated effect of ultrasonic energy on colloids of different stability. In removing turbidity, ultrasound exposure had the most favorable effect on aluminum sulfate. In respect of color, a better result was obtained using the modified coagulant. The possibility of reducing the coagulant dose confirmed the aiding effect of ultrasound. In the coagulation process, ultrasound exposure has a positive effect on the course of flocculation and the sedimentation of suspensions. In addition to the reduction in the doses of chemical reagents, it also leads to the modification of the post-coagulation sludge structure. Full article
Show Figures

Figure 1

10 pages, 2888 KB  
Article
Optically Controlled TiO2-Embedded Supercapacitors: The Effects of Colloidal Size, Light Wavelength, and Intensity on the Cells’ Performance
by Haim Grebel and Tazima Chowdhury
Nanomaterials 2022, 12(11), 1835; https://doi.org/10.3390/nano12111835 - 27 May 2022
Cited by 2 | Viewed by 2167
Abstract
Optically controlled supercapacitors (S-C) could be of interest to the sensor community, as well as set the stage for novel optoelectronic charging devices. Here, structures constructed of two parallel transparent current collectors (indium-tin-oxide, ITO films on glass substrates) were considered. Active-carbon (A-C) films [...] Read more.
Optically controlled supercapacitors (S-C) could be of interest to the sensor community, as well as set the stage for novel optoelectronic charging devices. Here, structures constructed of two parallel transparent current collectors (indium-tin-oxide, ITO films on glass substrates) were considered. Active-carbon (A-C) films were used as electrodes. Two sets of electrodes were used: as-is electrodes that were used as the reference and electrodes that were embedded with submicron- or micron-sized titanium oxide (TiO2) colloids. While immersed in a 1 M Na2SO4, the electrodes exhibited minimal thermal effects (<3 °C) throughout the course of experiments). The optically induced capacitance increase for TiO2-embedded S-C was large of the order of 30%, whereas S-C without the TiO2 colloids exhibited minimal optically related effects (<3%). Spectrally, the blue spectral band had a relatively larger impact on the light-induced effects. A lingering polarization effect that increased the cell capacitance in the dark after prolonged light exposure is noted; that effect occurred without an indication of a chemical reaction. Full article
Show Figures

Graphical abstract

13 pages, 4509 KB  
Article
Evolution of Electronic State and Properties of Silver Nanoparticles during Their Formation in Aqueous Solution
by Vadim Ershov, Natalia Tarasova and Boris Ershov
Int. J. Mol. Sci. 2021, 22(19), 10673; https://doi.org/10.3390/ijms221910673 - 1 Oct 2021
Cited by 22 | Viewed by 3966
Abstract
The electron density of a nanoparticle is a very important characteristic of the properties of a material. This paper describes the formation of silver nanoparticles (NPs) and the variation in the electronic state of an NP’s surface upon the reduction in Ag+ [...] Read more.
The electron density of a nanoparticle is a very important characteristic of the properties of a material. This paper describes the formation of silver nanoparticles (NPs) and the variation in the electronic state of an NP’s surface upon the reduction in Ag+ ions with oxalate ions, induced by UV irradiation. The calculations were based on optical spectrophotometry data. The NPs were characterized using Transmission electron microscopy and Dynamic light scattering. As ~10 nm nanoparticles are formed, the localized surface plasmon resonance (LSPR) band increases in intensity, decreases in width, and shifts to the UV region from 402 to 383 nm. The interband transitions (IBT) band (≤250 nm) increases in intensity, with the band shape and position remaining unchanged. The change in the shape and position of the LSPR band of silver nanoparticles in the course of their formation is attributable to an increasing concentration of free electrons in the particles as a result of a reduction in Ag+ ions on the surface and electron injection by CO2 radicals. The ζ-potential of colloids increases with an increase in electron density in silver nuclei. A quantitative relationship between this shift and electron density on the surface was derived on the basis of the Mie–Drude theory. The observed blue shift (19 nm) corresponds to an approximately 10% increase in the concentration of electrons in silver nanoparticles. Full article
(This article belongs to the Special Issue Nano-Materials and Methods 3.0)
Show Figures

Figure 1

Back to TopTop