Capparis spinosa (CS) was extracted by the soxhlet extraction method using ethanol as the extractant. The TiO2/CS composite was synthesized by the in situ solvothermal method with CS extract as a dopant. The morphology, crystal structure, and optical properties of TiO2/CS were characterized by SEM, TEM, XRD, UV-Vis and FT-IR spectroscopy. The experimental results showed that TiO2/CS exhibited excellent photoresponse performance, generated active free radicals, and achieved photocatalytic degradation of organic pollutants. Furthermore, TiO2/CS served as antibacterial agents to evaluate their antibacterial properties against Escherichia coli (E. coli) at different concentrations. The results showed that TiO2/CS possessed excellent antibacterial performance and produced a significant antibacterial ring, with antibacterial rate of about 100% after being diluted 100 and 500 times, respectively. The test results indicated that TiO2/CS has great application potential in the field of antibacterial activity and photocatalytic degradation, owing to its advantages of being natural, environmentally friendly, and economical.
In addressing the concerns regarding structural performance degradation and diminished service life resulting from concrete crack formation during utilization, this study has developed a cement-based self-healing material. This material utilizes a composite complexing agent composed of tartaric acid derivatives, sodium hexametaphosphate, ethylenediaminetetraacetic acid tetrasodium salt, and vinyl acetate-ethylene redispersible latex powder. The material composition was optimized, and its self-healing performance and mechanism were systematically studied. The findings indicated that when the composite complexing agent content was set at 6% by mass of cement, there was a substantial decrease in the porosity, from 34.2% to 14.2%. In comparison with the control group, specimens with a 6% composite complexing agent exhibited an 8.3 MPa increase in compressive strength and a substantial enhancement in crack sealing, with a rate increase from 73.1% to 99.7%, following 28 days of water curing.
A new temporary plugging agent was developed to solve the problem of insufficient plugging performance of existing gel profile control and water shutoff. The organic material with temperature sensitivity and phase change function is assembled on the surface of the matrix material with high stability and good plugging performance by multi-layer assembly technology, and the composite gel profile control agent with multi-level structure is prepared. Research shows that the prepared profile control agent has a certain salt tolerance, and the inhibitory effect of CaCl2 is greater than that of NaCl. When the C25H(52) content is 3.6%, the multi-layer assembled profile control agent prepared by it has the best water absorption performance. When the temperature is 60 C-o, the multi-layer assembled paraffin profile control agent prepared has the best water absorption effect.
Epoxy resin (EP) has been widely used in many fields due to its excellent physical and chemical properties. However, its inherent flammability limits its application in some fields, and the development of efficient and environmentally friendly new flame retardants has become a research hotspot. In recent years, researchers have been committed to developing new flame retardants to improve the flame retardant properties of EP. The development of synergistic flame retardant systems, combined with the advantages of various flame retardants, has become a research trend. In this paper, the application progress of three kinds of new flame retardants in EP, including nano-materials, organic materials, and inorganic materials, is summarized. Their synthesis methods, structural design, and application prospects are compared, and a summary and prospect are given.
The processing of waste cooking oils (WCO) is a complex process that heavily depends on their chemical and physical properties. The work described in this article includes research on the processing of WCO samples using transesterification methods. An automated reactor system Matrix9 HAAS was used to perform process studies and FT-IR measurements. Transesterification of oils in the presence of KOH might be directly applied as the optimal one for oils with a low acid number, while for oils with a higher acid number an additional esterification step is advisable in the presence of an acid catalyst or under conditions of high temperature and pressure.
Thanaka powder is a natural and safe biomass material that can be used in the preparation of Pickering emulsions. It contains lots of hydrophilic phenolic hydroxyl groups, making it highly hydrophilic and leading to emulsion instability, which further limits its application in the cosmetics industry. In this paper, Thanaka powder was modified to improve its stability. The modified Thanaka powder was characterized and was used to prepare Pickering emulsions. The results showed that the stability of the Pickering emulsion increased with the increase of the solid particle concentration; the suitable oil-water ratio helped to obtain the Pickering emulsion with good stability; the different aqueous phase environments had little effect on the particle size variation of the emulsified particles; the emulsions exhibited shear thinning behavior. This study offers valuable insights into the research, development, and commercialization of Thanaka-based skincare products, thereby expanding the applications of Thanaka powder.
A new type of self-healing gel was developed by using acrylamide (AM) and other materials, and the effects of the content of PEGDA200 and PEGDA400 on the mechanical properties of gel were compared. The results showed that adding PEGDA200 and PEGDA400 to the self-repairing gel significantly improved the performance of the composite gel. When the content of PEGDA200 in the gel was 0.2%, the rheological property after repair was 109.4% of that before repair, the compressive property after repair was 95.2% of that before repair, the adhesive property was increased by 36.8%, and the compressive strength after repair was 92.4% of that before repair. When the content of PEGDA400 in gel was 0.2%, the rheological property of gel after repair was 105.8% of that before repair, the maximum adhesion could be increased by 17.8%.
The aim of the research was to develop and evaluate the usefulness of artificial neural network models for predicting the key operating parameters of centrifugal settlers. Various settler structures were analyzed, taking into account such elements as internal partitions and also inlet and outlet nozzles. Neural network modeling was continued until the highest possible quality was achieved in terms of training, testing and validation, with the occurrence of errors also being minimized. This process involved multiple iterations and adjustments of the network’s parameters to achieve optimal results. It was shown that artificial neural networks are characterized by having high accuracy in predicting the efficiency and damming values of centrifungal sedimentation tanks with regards to their design and hydraulic load. The designed network is able to determine both efficiency and liquid level with satisfactory accuracy.
In the study, the catalytic pyrolysis behavior of low-rank Umutbaca coal with the addition of CaO was examined using thermal analysis methods. For this purpose, the effect of adding CaO to coal on both the pyrolysis temperatures of the coal and the composition of the gas and solid product (char) was investigated. Also, the kinetic analysis was carried out to characterize the catalytic pyrolysis process by adding CaO to coal. Using the data obtained in TGA at heating rates of 2.5, 5, and 10 °C/min, the activation energies required for the pyrolysis process of coal both with and without CaO were calculated by KAS and FWO methods. Thermodynamic parameters including ∆H, ∆G, and ∆S were calculated with activation energies obtained from the FWO method. The thermodynamic suitability of adding CaO to a low rank coal such as Umutbaca for the pyrolysis process was investigated.
Pulsed laser ablation in liquid (PLAL) is one of the main techniques for synthesizing nanoparticle materials. The carbon target was dissolved in ultrapure water (UPW) and exposed to a Q-switched Nd: YAG laser (1064 nm) with a 6 ns pulse duration to produce carbon nanoparticles. In this sequence, the Nd: YAG laser beam was focused on the carbon surface. In the investigation of nanoparticles prepared by laser irradiation, the effect of different incident laser pulse energies (500, 1000 mJ) on particle sizes (52.09, 26.49 nm) was observed by atomic force microscopy (AFM), pH test, and lightning energy conductivity (EC) test of nanosolution was used to characterize the nanoparticles. Particle size was generated using (1000 mJ) laser pulse energy. The performance of the H-shaped microbial fuel cell (MFC) was also tested, using nanocolloids in a salt bridge. This work shows that (Co) NPs synthesized with an energy of (1000 mJ) pulsed laser can act as salt bridge catalysts to improve MFC power output.
Solvent extraction technology was applied to extract fluorosilicic acid from aqueous solution with trioctylamine (TOA) as extractant. The extraction mechanism of fluorosilicic acid with TOA was studied via stoichiometry methods combined with spectroscopic methods. The results of saturation capacity method and equimolar methods showed that there were two kinds of organic extracts produced with molar ratio of 1: 1 and 2: 1 in the system, whose chemical formulas were (R 3 N · H 2 SiF 6 ) 3 and [(R 3 N) 2 · H 2 SiF 6 ] 2 , respectively. Fuorosilicic acid was extracted with TOA via hydrogen bonds. The liquid-liquid phase equilibria of the ternary system fluorosilicic acid (1)-water (2)-TOA (3) from 283.15 K to 323.15 K were determined. The equilibrium phase diagram of the ternary system is obtained. The partition coefficient and separation factor were calculated to evaluate the extraction capacity of TOA for fluorosilicic acid, which showed that TOA exhibited high selectivity.
The article explores the impact of various factors on the determination of gas bubble equivalent diameters using optical shadowgraphy. The experimental setup involves a liquid-gas system. The results indicate that the distance between the camera and the bubble rise-up plane has negligible influence on measurement precision as long as the area captured is constant. Increasing the number of analyzed frames significantly reduces uncertainties, while higher image magnification leads to increased uncertainties due to a reduced number of frames and smaller area captured. Image distortion correction minimally affects results and precision. The study concludes that factors such as resolution, frame rate, and elongated flow path captured contribute to more accurate determination of equivalent bubble diameters, essential for the determination of mass and heat transfer coefficients in liquid-gas flows. The results indicate that a sufficiently high number of video frames may be more important than indiscriminately increasing the resolution.
In this study, chlorophenyl-substituted pyrazolone derivatives (5a-5c) were synthesized via the Baylis-Hillman acetate reaction. Comprehensive physicochemical characterization was conducted using 1H-NMR, FT-IR, and mass spectroscopy. Density Functional Theory (DFT) calculations at the B3LYP/6-31(G) level was employed to optimize molecular geometries and investigate electronic properties, revealing predominantly planar structures, with notable deviations in the pyrazole group. The HOMO and LUMO analyses showed pi-delocalization across the entire molecule, with charge-transfer transitions dominating the excited states. Global Chemical Reactivity Descriptors (GCRD), including chemical potential, hardness, and electrophilicity index, were used to assess molecular stability and reactivity, indicating the molecules' resistance to electron cloud deformation. Biological evaluations revealed exceptional antimicrobial and antifungal activities of the derivatives, with compound 5a demonstrating the highest efficacy against S. aureus, E. coli, A. niger and C. albicans. Furthermore, antiproliferative studies against HepG2 liver carcinoma cells showed that compound 5a exhibited superior anticancer activity (IC50 = 6 mu g/mL), attributed to its structural features, such as chlorophenyl groups and a piperidin-4-one moiety. These moieties enhance the compound's lipophilicity, facilitating cell membrane penetration and ROS generation, which contribute to apoptosis and inhibition of cancer cell growth. The findings suggest that chlorophenyl-pyrazolone derivatives, particularly 5a, hold promise as potent candidates for antimicrobial and anticancer therapies, paving the way for further pharmaceutical development.
In free radical polymerization initiated by 2,2’-azobis(2-methylpropionamidine) dihydrochloride, grafted starch copolymers with a weight ratio of acrylamide to acrylic acid of 1:2 were obtained. Three acrylic products were used to cross-linking starch copolymers: MBA, PETIA and EBECRYL 40 in amounts of: 0.2, 0.4, 0.6 and 1.0 wt.%. Materials were characterized by Fourier transform infrared spectroscopy, differential scanning calorimetry and reoviscometry. The sorption properties of starch copolymers were confirmed by sorption tests: water absorption, swelling in water and sorption of cations: trivalent iron and divalent copper. The highest water absorption is characteristic of materials cross-linked with MBA (1800%), then PETIA (1400%) and EBECRYL 40 (850%). On the other hand, the best swelling results are in the sequence PETIA > MBA > EBECRYL (1050% > 900% > 570%). The most effective sorbent of cations is the copolymer cross-linked with MBA. Solution purifications of 90% and 45% were obtained for Fe+3 and Cu+2, respectively.
The aim of this study was to characterize the bioactive components in avocado oil (AVO) extracted by ultrasound combined with microwave, which are clean technologies used to assess oil quality. AVO samples were incubated for 30 min at 120 degrees C (T1), 180 degrees C (T2), and without any heat treatment (T3). Components were identified using chromatographic techniques, Raman spectroscopy, and thermogravimetric analysis (TGA). gamma-Tocopherol and total carotenoids were affected in T2. The Raman spectrum of T3 and T1 presented a strong band at 1265 cm-1 related to the high content of linoleic acid and three bands associated with carotenoids. In the T2 sample, a weak intensity of the linolenic and linoleic acids was observed. In TGA, T2 showed a robust mass at 173.89 degrees C, characteristic of oxidized oil compounds. AVO treated at 120 degrees C for 30 min maintained the integrity of the bioactive compounds.
The work presented a facile, one-step procedure as a green assembly process for preparing silver tungstate nanorod by hydrothermal technique via a chemical reaction between silver nitrate and sodium tungstate. The synthesized precipitate was characterized using X-ray diffraction (XRD) transmission electronic microscope (TEM) and scanning electron microscopy (SEM) to ensure the formation of crystallization and single-phase material. The prepared nanorods undergo a catalytic evaluation to synthesize tetrahydrobenzo[a] xanthene-11-one derivatives by a one-pot reaction of beta-naphthol, dimedone, and aromatic aldehyde with a catalytic amount of silver tungstate under the solvent-free condition at 60-70 degrees C. ArgC is one of the L-arginine biosynthetic pathways of mycobacterium tuberculosis. The molecular docking explains that all the synthesized compounds presented high ligand ability for the targeted enzyme compared with xanthene-9-carboxylic acid as a reference.
The tests were carried out for the selected 27MnCrB5-2 alloy steel with the addition of boron. The paper presents the kinetics of the ferritic transformation occurring under continuous cooling conditions. The temperatures of the beginning and end of the transformation of supercooled austenite were determined using a dilatometer. In addition, a waveguide and an acoustic sensor were installed in the device to receive acoustic emission signals. The results in the form of dilatometric curves were additionally confirmed by the obtained acoustic emission signals. Based on the obtained microstructural results, it can be concluded that in the hardening process of 27MnCrB5-2 steel at the applied temperatures, complex transformations of austenite into ferrite and bainite occur. The use of acoustic methods in the field of phase transformation issues creates the possibility of their application in industry.
Completely symmetrical 6,6’-cyclohexane-1,1-diyl bis (3-substituted-3,4-dihydro-2H-1,3-benzoxazine) synthesized compounds have been able by a two-step process that yields a large amount of the compound. First, phenol and cyclohexanone were subjected to the Friedel-Craft process to produce 1,1’-bis(4-hydroxyphenyl) cyclohexane. The reaction between the bisphenol and formaldehyde and several primary amines produced unique symmetrical 1,3-benzoxazine compounds. Several spectroscopic methods, such as Fourier transform infrared spectroscopy, nuclear magnetic resonance (1H and 13C), GCMS spectrometry, and CHNS, were utilized in conjunction with tridimensional liquid chromatography (TLC) to investigate and validate the structures of the compounds created thoroughly. Two Gram-negative and two Gram-positive bacteria and a pathogenic fungus were tested for antimicrobial activity in contrast to the gold-standard medications streptomycin and nystatin. The antibacterial activity of some of these compounds was even better than that of the gold-standard medications, which is encouraging.
The article discusses radial mixing in a Horizontal Aerated Tubular Reactor (HATR). The study aimed to experimentally investigate mixing in HATR by determining mixing time, liquid circulation time, and Peclet number values, which measure the ratio of advective to diffusive transport rates. The experimental setup included a transparent tube for observing fluid mixing and a color tracer was used for visualizing mixing. Mixing and circulation times were determined using non-intrusive optical method. The experimentally determined circulation time was in the range of 3 divided by 6.5 s, and the mixing time was in the range of 5 divided by 20 s. The results suggested that fluid flow structure in HATR was closer to plug flow rather than ideal mixing, as indicated by high Peclet numbers (20 divided by 45).
Sodium metasilicate (SMS) tended to agglomerate during glycerolysis reactions in high shear compartment reactors (HSCR), hindering triacylglycerol (TAG) conversion. Therefore, the aim was to evaluate the SMS-magnesium oxide (MgO) blend as a heterogeneous catalyst for glycerolysis reactions. Various SMS-MgO ratios (ranging from 2.5:1 to 10.0:1) were evaluated. The results demonstrated that increasing MgO in the blend reduced catalyst basicity and minimized O-Si-O groups and catalyst crystallinity, preventing clumping and increasing catalyst surface area. The SMS-MgO 5.0:1 blend exhibited the smallest pore size (<2 nm) with a surface area of 4.22 m(2) .(-1)( g) and basicity of 11.59 +/- 0.115 mmol . g(-1). This blend achieved the highest TAG conversion of 53.98%, with a MAG content of 16.86 +/- 0.528% when it was performed at 120 degrees C with an agitator speed of 2,000 rpm for 6 h. Thus, the SMS-MgO 5.0:1 blend shows promise as a heterogeneous catalyst in glycerolysis reaction in HSCR, hindering agglomeration and enhancing surface area.
