Ultrasonic Aid Research Articles

Forming a disordered atomic layer to bond TiN or AlN ceramic with Sn[sbnd]9Zn metal under ultrasonication

A disordered atomic layer instead of traditional intermetallic compounds is formed in the bonding interface of ceramic and metal in the metallization of ceramics under ultrasonication. A deep understanding of the bonding mechanism between poor-wetted ceramics and low-temperature metals remains limited with regard to high metallization efficiency and nanoscale bonding structure. In this work, the metallization of AlN and TiN ceramics was realized using Sn9Zn metal with the aid of ultrasonication. The microstructure, energy, and element sources of the ceramic/metal interface were analyzed. Results show that a nanoscale amorphous layer is formed between the ceramics and the metal, and this layer can bond easily with AlN or TiN and Sn9Zn because of the irregular arrangement of its atoms. Some dispersed nanocrystals are also present in the amorphous bonding layer. The thermal effect of ultrasonic cavitation produces a high temperature above 106 K, which provides the energy for the bonding of AlN or TiN with Sn9Zn. O and Zn accumulate in the Sn-9Zn/AlN bonding layer. Zn originates from Sn9Zn. O could be from the O2 dissolved in the liquid solder or the O2 adhering to the ceramic. A small amount of AlN decomposes because of its high ΔG of decomposition. However, TiN decomposes into Ti and N2 under the extreme condition caused by ultrasonic cavitation. The accumulated Ti in the Sn-9Zn/TiN bonding layer originates from TiN. The source of the accumulated O is the same as that of Sn-9Zn/AlN bonding layer.

Fabrication of 3D framework of KIT-6 with CuO NPs for catalytic reduction of 4-nitrophenol and methylene blue

Cu-containing catalysts are highly active for catalytic conversion of nitrophenols and azo dyes due to their low cost and high efficiency. However, the activity is dependent on the dispersion and size of Cu nanoparticles (NPs). Herein, well dispersed Cu NPs were formed in the nanoconfinements of KIT-6 via IWI with ultrasonic aid. The materials were characterized by FT-IR, SEM, ICP-OES, XRD, TEM, UV–vis DRS, N2 adsorption–desorption, and elemental mapping. Characterization results revealed that Cu content up to 10 wt% is highly dispersed with smaller size over KIT-6 and improved the hydrogenation performance. Among tested catalysts, 10Cu/KIT-6 exhibited extraordinary activity for conversion of 4-nitrophenol (4-NP) (1506 mmole h−1 g−1) and methylene blue (MB) (237 mmole h−1 g−1) in water. Catalytic conversion of 4-NP and MB obey pseudo first-order kinetics, and the activity is correlated with excellent characteristics of Cu/KIT-6. Besides, the 10Cu/KIT-6 displayed similar activity after 6th cycles.

Design and Effect of Resonant Ultrasonic Vibration-Assisted Laser Cladding (R-UVALC) on AlCrFeMnNi High-Entropy Alloy.

The design of the resonant ultrasonic vibration-assisted laser cladding (R-UVALC) setup involved employing finite element analysis (FEA) to simulate the ultrasonic transducer, horn, and workpiece in a resonance state. The impact of R-UVALC on AlCrFeMnNi high-entropy alloys was assessed using various ultrasonic vibration amplitudes of 0, 5, 10, and 15 µm, with a constant frequency of 20 kHz. Ultrasonic vibrations reduced pores and cracks and increased the clad breadth, melt pool wetting angle, and laser-clad layer consistency. The columnar elongated grains in proximity to the substrate surface underwent a size reduction and transformed into grains with a more equiaxed shape with the utilization of ultrasonic vibrations at an amplitude of 5 µm. Laser cladding performed without ultrasonic vibrations yields two phases: face-centered cubic (FCC) and body-centered cubic (BCC). However, when the coating is exposed to ultrasonic vibrations with an amplitude of 5 µm, it forms a solitary body-centered cubic (BCC) phase. The microhardness tripled compared to the substrate, and the most significant microhardness value was achieved at 5 µm of ultrasonic vibration. The friction coefficient was assessed at an ambient temperature, revealing that an ultrasonic amplitude yields the lowest friction coefficient, demonstrating the excellent wear resistance properties of the coating. The analysis of the 3D surface profile of the wear indicates that the use of ultrasonic aid with a 5 µm amplitude leads to reduced depth of scars, and the primary wear mechanism observed is abrasive and oxidative wear with fewer grooves and debris. In addition, XPS analysis revealed the presence of metal components in an oxidized condition, suggesting that the wear process is oxidative in nature. Integrating the R-UVALC setup into a resonance state can significantly enhance the efficiency of the laser cladding process in the laser cladding field.

Ethanolic cashew leaf extract: Antioxidant potential and impact on quality changes of dried fermented catfish during storage

Ethanolic cashew (Anacardium occidentale, L.) leaf extract (ECLE) rich in phenolic compounds was prepared with the aid of ultrasonication. Impacts of light, heat, and pH on stability of antioxidant activity of ECLE were investigated. Exposure to light at an intensity of 1000 lx for 24 h showed no effect on activity of ECLE (p > 0.05). When being exposed to light for an extended periods (48 h), total phenolic content (TPC) became lower (p < 0.05). Light intensities at 2400–4000 lx for 24 h significantly decreased TPC and reduced antioxidant activities (p < 0.05). Thermal treatment at 60–100 ̊C for 1 h plausibly induced decomposition and simultaneously released low-molecular-weight phenolic compounds, leading to an increase in activity (p < 0.05). ECLE showed the augmented antioxidant activity in pH range of 3–5. When ECLE was added to dried fermented catfish (DFC) at 200–600 mg/kg and stored for 21 days at 30 ̊C, ECLE at 600 mg/kg effectively retarded lipid oxidation and inhibited the growth of microorganisms of DFC during storages, thereby extending the shelf life of DFC. ECLE could therefore be utilized as natural food additive or preservative in DFC.

Ultra-trace analysis of chromium ions (Cr3+/Cr6+) in water sample using selective fluorescence turn-off sensor with natural carbon dots mixed graphene quantum dots nanohybrid composite synthesis by pyrolysis

This study was aimed to implement the one-pot pyrolysis for hybrid nanomaterial synthesis consisting of graphene quantum dots (GQDs) from solid citric acid and carbon dots (CDs) which was hydrothermally derived from the herbal plant extract of “Houttuynia cordata”, denoted as Carbon Dots mixed Graphene Quantum Dots (CDs@GQDs). The nanohybrid were structurally characterized by XPS, FT-IR, Fluorescence, and UV–Visible absorption spectroscopy, and their morphological images were also analyzed by HR-TEM and FE-SEM/EDX. The quantum yield was found to be 15 %, higher than that of intact CDs or GQDs. Upon excitation at a maximum wavelength of 355 nm, and emission in the 450 nm. In this case, it was observed that the nanohybrid exhibit a high degree of selectivity towards Cr6+ ion when employed as a fluorescence quenching sensor from screening test with different metal ions. Therefore, the optimization conditions of solution pH, concentration of nanohybrid, H2O2 concentration as an oxidizing agent, reaction duration time with the aid of ultrasonication were carried out in details and the permissible limit of Cr3+ presence in the target analyte was all undertaken in order to enhance the detection of Cr6+ species. Its linear calibration curve was such y = 0.37x + 55.7, with a coefficient of determination (r2) value of 0.9816. The limit of detection (LOD) and limit of quantification (LOQ) was found to be 17.2 nM, and 52.2 nM. Consequently, the nanohybrid as a green chelating agent in the selective assessment of ultra-trace amount of Cr6+ in spiked water sample model was also done with good recoveries in both bottled drinking water and tap water samples ranging from 102.86 to 114.23 %.

Ultrasound‐Triggered Surface Reconstruction with Improved Carriers Transfer Kinetics in CdIn2S4 for Solar Water Oxidation

AbstractThe surface oxygen evolution reaction (OER) is severely restricted owing to the sluggish OER kinetics and limited number of reactive sites. Although surface reconstruction can introduce defects to improve the OER performance, they often function as recombination centers and cause severe carrier recombination. With the aid of ultrasonication, the CdIn2S4 photoanode surface is reconstructed using Zn‐modified Cd defects without extreme chemical reaction environment. Owing to the surface reconstruction, the formed type‐II band structure is beneficial for separating photogenerated carriers and reduced the bulk recombination. Additionally, the Zn‐modified Cd defects are introduced in situ during the ultrasound cavitation process, which facilitated the carrier transfer, reduced the surface recombination, and increased the number of surface active sites. First‐principles calculations indicate that the modified Cd defects effectively lower the electrochemical reaction barrier and promote the surface OER kinetics by precisely regulating the four‐electron reaction. Consequently, the optimized photoanode exhibits a enhanced photocurrent of 5.30 mA cm−2 at 1.23 V versus reversible hydrogen electrode. These results demonstrate that an accurate surface reconstruction design can be achieved for introducing and modifying metal defects to improve the transfer and transport behaviors of photogenerated carriers.

Adapting the Time-Domain Synthetic Aperture Focusing Technique (T-SAFT) to Laser Ultrasonics for Imaging the Subsurface Defects.

Traditional ultrasonic testing uses a single probe or phased array probe to investigate and visualize defects by adapting certain imaging algorithms. The time-domain synthetic aperture focusing technique (T-SAFT) is an imaging algorithm that employs a single probe to scan along the test specimen in various positions, to generate inspection images with better resolution. Both the T-SAFT and phased array probes are contact methods with limited bandwidth. This work aims to combine the advantages of the T-SAFT and phased array in a noncontact way with the aid of laser ultrasonics. Here, a pulsed laser beam is employed to generate ultrasonic waves in both thermoelastic and ablation regimes, whereas the laser Doppler vibrometer is used to acquire the generated signals. These two lasers are focused on the test specimen and, to avoid the plasma and crater influence in the ablation regime, the transmission beam and reception beam are separated by 5 mm. By moving the test specimen with a step size of 0.5 mm, a 1D linear phased array (41 and 43 elements) with a pitch of 0.5 mm was synthesized, and three side-drilled holes (Ø 8 mm-thermoelastic regime, Ø 10 mm and Ø 2 mm-ablation regime) were introduced for inspection. The A-scan data obtained from these elements were processed via the T-SAFT algorithm to generate the inspection images in various grid sizes. The results showed that the defect reflections obtained in the ablation regime have better visibility than those from the thermoelastic regime. This is due to the high-amplitude signals obtained in the ablation regime, which pave the way for enhancing the pixel intensity of each grid. Moreover, the separation distance (5 mm) does not have any significant effect on the defect location during the reconstruction process.

Effect of green synthesized zinc oxide nanoadditives and rice bran oil biodiesel blend on performance and combustion characteristics of a variable compression ratio diesel engine: an experimental study

AbstractThe aim of this research was to investigate experimentally the performance and combustion characteristics of a four‐stroke, single‐cylinder, water‐cooled variable compression ratio diesel engine using rice bran oil biodiesel blends with zinc oxide nanoparticles. Rice bran oil biodiesel was prepared using a transesterification reaction with a 6:1 methanol‐oil molar ratio and 1% w/w potassium hydroxide as catalyst. Zinc oxide nanoparticles were synthesized using a green method incorporating Psidium guajava leaf extract as a capping agent to reduce precursor use and to reduce the toxicity of the nanomaterial. The synthesized zinc oxide nanoparticles were characterized by using X‐ray diffraction and Fourier‐transform infrared spectroscopy to confirm the formation of highly crystalline pure zinc oxide nanoparticles with a hexagonal wurtzite crystal structure with an average diameter of 20.963 nm. Rice bran‐oil biodiesel‐diesel blend was prepared by volumetrically mixing 20% biodiesel and 80% mineral diesel and was considered as a base fuel for comparison. Zinc oxide nanoparticles were diffused in the base fuel at dosage levels of 25, 50, and 75 ppm, with the aid of ultrasonication. Measurement of the major physicochemical properties of test fuels showed an increase in the cetane number and calorific value and a reduction in viscosity with an increase in the zinc oxide concentration. The overall properties of all the test fuels were found to be similar in comparison with commercial diesel. An experimental engine test was carried out under different loading conditions with a constant speed of 1500 RPM and two different compression ratios – that is, 17.5:1 and 15:1. Among all the test fuels at both compression ratios, engine performance and combustion properties improved with an increase in the zinc oxide concentration. Test fuel with 75 ppm of zinc oxide additive at 17.5 compression ratio resulted in an overall improvement at full load: brake thermal efficiency increased by 2.45%, brake specific fuel consumption reduced by 5.45%, cylinder peak pressure increased by 3.27% and net heat release increased by 10.32% in comparison with base fuel.

Ultrasound-Assisted Extraction of Phenolic Compounds from Red Jute (Corchorus olitorius L.) Leaves Using Aqueous Ethanol

Extraction of bioactive components from natural sources has recently gained interest due to their medicinal benefits. Jute or “saluyot,” a fast-growing perennial herb abundant in the Philippines, is known to have high nutritive value and is a good source of phenolic compounds. This study focused on the optimization of the ultrasound-assisted extraction of the antioxidant phenolic compounds from red jute (Corchorus olitorius L.) using aqueous ethanol. Characterization of fresh jute leaf samples showed that jute leaf contains 84.52 ± 0.00% w/w moisture, 3.81 ± 0.98% w/w extractives, 11.67 ± 0.98% w/w total solids and total phenolic content (TPC) of 17.72 ± 0.36 mg gallic acid equivalent (GAE)/gram bone dried leaves (gdl). Screening of the five factors (extraction temperature, extraction time, particle size, solid to solvent ratio and ethanol concentration) showed that extraction temperature, extraction time and ethanol concentration significantly affected the TPC of the extracts. Likewise, the interaction of particle size and ethanol concentration (negative effect) is significant. The optimum conditions were found to be 50 oC extraction temperature, 20 min extraction time and 69.037% ethanol using suggested quadratic equations obtained through the models generated via Central Composite Design. Optimum TPC was 15.08 ± 0.03 mgGAE/gdl and optimum percent recovery was 85.11 ± 0.17%. Small percent differences (0.80% both) with respect to predicted suggest high desirability of the model equations. The high recovery of phenolic compounds with the aid of ultrasonication even at one extraction cycle is therefore proven to be significant, suggesting the potential of jute as source of phenolic compounds

Nanofluids of Amphiphilic Kaolinite-Based Janus Nanosheets for Enhanced Oil Recovery: The Importance of Stable Emulsion.

To meet the increasing global demand for energy, better recovery of crude oil from reservoirs must be achieved using methods that are economical and environmentally benign. Here, we have developed a nanofluid of amphiphilic clay-based Janus nanosheets via a facile and scalable method that provides potential to enhance oil recovery. With the aid of dimethyl sulfoxide (DMSO) intercalation and ultrasonication, kaolinite was exfoliated into nanosheets (KaolNS) before being grafted with 3-methacryloxypropyl-triemethoxysilane (KH570) on the Alumina Octahedral Sheet at 40 and 70 °C to form amphiphilic Janus nanosheets (i.e., KaolKH@40 and KaolKH@70). The amphiphilicity and Janus nature of the KaolKH nanosheets have been well demonstrated, with distinct wettability obtained on two sides of the nanosheets, and the KaolKH@70 was more amphiphilic than the KaolKH@40. Upon preparing Pickering emulsion in a hydrophilic glass tube, the KaolKH@40 preferentially stabilized emulsions, while the KaolNS and KaolKH@70 tended to form an observable and high-strength elastic planar interfacial film at the oil-water interface as well as films climbing along the tube's surface, which were supposed to be the result of emulsion instability and the strong adherence of Janus nanosheets towards tube's surface. Subsequently, the KaolKH was grafted with poly(N-Isopropylacrylamide) (PNIPAAm), and the prepared thermo-responsive Janus nanosheets demonstrated a reversible transformation between stable emulsion and the observable interfacial films. Finally, when the samples were subjected to core flooding tests, the nanofluid containing 0.01 wt% KaolKH@40 that formed stable emulsions showed an enhanced oil recovery (EOR) rate of 22.37%, outperforming the other nanofluids that formed observable films (an EOR rate ~13%), showcasing the superiority of Pickering emulsions from interfacial films. This work demonstrates that KH-570-modified amphiphilic clay-based Janus nanosheets have the potential to be used to improve oil recovery, especially when it is able to form stable Pickering emulsions.

Effect of hydrogen enrichment and TiO2 nanoparticles on waste cooking palm biodiesel run CRDI engine

In this study, we deal with the production and utilization of waste-cooking palm biodiesel (WCB) and.evaluated the influence of the addition of titanium dioxide (TiO2) nanoparticles in hydrogen-enriched single-cylinder CRDI diesel engine. XRD, SEM, and EDX decide the structure and morphology of TiO2 nanoparticles. The TiO2 nanoparticles were dispersed in the tested fuels at a dosage of 50–75 ppm with the aid of ultra-sonication. Based on the oxidation stability study, the B20 + 75 ppm (TiO2) fuel blend is the pilot fuel for the engine test. Further, the engine is enriched with a hydrogen (H2) flow of 10 lpm. Results revealed that the performance parameters were improved with the addition of H2 enrichment and TiO2 nanoparticles compared to D. The brake thermal efficiency of the engine was improved by 8.21%. In comparison, brake-specific fuel consumption decreased by 42.86%. Furthermore, adding nanoparticles also reduced CO and HC emissions by 74% and 27.27%, respectively, whereas the NOx emission was slightly increased. Thus, the findings demonstrated that hydrogen-enriched nanoparticles added to biodiesel might be considered a substitute for fossil fuels and report a positive impact on diesel engine performance without requiring significant modifications.

Cu nanoparticles confined within ZSM-5 derived mesoporous silica (MZ) with enhanced stability for catalytic hydrogenation of 4-nitrophenol and degradation of azo dye

The development of cost effective and efficient non-noble metal catalysts is extremely desirable in recent years for reduction of toxic nitrobenzene and azo compounds. In this work, highly reactive Cu nanoparticles (NPs) were constructed in mesoporous silica (MZ) synthesized using ZSM-5 (Si/Al = 28) via hydrothermal crystallization strategy and then tested as catalyst in the catalytic hydrogenation of 4-nitrophenol (4-NP) and methylene blue (MB) degradation to reduce their hazardous effect on environment. In comparison with ZSM-5, MZ with hierarchical pore structure effectively controls the size and dispersion extent of Cu NPs when fabricated with 5-15 wt%Cu via IWI with ultrasonic aid. Cu10/MZ displayed complete reduction of 4-NP to 4-aminopheneol (4-AP) and MB dye to LMB in 10 min with K (rate constant) value of 0.298 min and 0.65 min−1, respectively. Both catalytic conversions follow pseudo-first order kinetics. The high catalytic activity is evidently related with highly dispersive smaller sized Cu NPs and excellent physiochemical characteristics of MZ as demonstrated by various characterization techniques. Besides, the Cu/MZ catalyst displayed excellent stability and can be applied for 5 consecutive reduction cycles without any minimal loss in catalytic capabilities.

Facile, Controllable, and Ultrathin NiFe-LDH In Situ Grown on a Ni Foam by Ultrasonic Self-Etching for Highly Efficient Urine Conversion.

As the primary source of nitrogen pollutants in domestic sewage, urine is also an alternative for H2 production via electrochemical processes. However, it suffers from sluggish kinetics and noble-metal catalyst requirement. Here, we report a non-precious ultrathin NiFe-layered double hydroxide catalyst for the remarkable conversion of urea into N2 and H2, which is in situ grown on a Ni foam via ultrasonic self-etching in Fe3+/ethylene glycol (EG). EG regulates the etching rate of Fe3+, resulting in an ultrathin nanosheet structure with the aid of ultrasonication. This structure dramatically promotes the dehydrogenation process via decreasing the nanolayer thickness from 120 to 3.4 nm and leads to a 4.8-fold increase in the generation of active sites. It exhibits record urea oxidation kinetics (390.8 mA·cm-2 at 1.5 V vs RHE) with excellent stability (120 h), which is 11.8 times better than that of commercial Pt/C catalyst (33.1 mA·cm-2). Tests with real urine at 20 mA cm-2 achieve 74% total nitrogen removal and 2853 μmol·h-1 of H2 production. This study provides an attractive landscape for producing H2 by consuming urine biowastes.

Comparative Evaluation of Hydrothermally Produced Rice Starch–Phenolic Complexes: Contributions of Phenolic Type, Plasma-Activated Water, and Ultrasonication

A thorough investigation of the viability of rice starch conjugation with three different phenolic compounds-gallic acid, sinapic acid, and crude Mon-pu (Glochidion wallichianum Muell Arg) (MP) extract-was conducted using a variety of developed methods which modified the techno-functionality and digestibility of the end product. With and without the aid of ultrasonication (US), phenolic compounds were complexed with hydrothermally pre-gelatinized rice starch prepared using distilled water or plasma-activated water (PAW). The in vitro digestibility, structural features, rheological and thermal properties, and in vitro antioxidant activity of starch-phenolic complexes were evaluated. The US-assisted starch-MP complex in water had the highest complexing index (CI) value (77.11%) and resistant starch (RS) content (88.35%), resulting in a more compact and stable ordered structure. In all complexes, XRD revealed a new minor crystalline region of V-type, which was stabilized by hydrogen bonding as defined by FTIR and H1-NMR. Polyphenols caused a looser gel structure of starch, as imaged by a scanning electron microscope (SEM). Starch-phenolic complexes outperformed other complexes in terms of in vitro antioxidant activity. Gallic acid addition to starch molecules boosted DPPH scavenging activity, notably when synthesized in PAW regardless of US assistance, although having lower CI and RS values than the MP complex. Therefore, this research lays the groundwork for the efficient production of functional food ingredients based on rice starch and polyphenols.

Ethanolic Cashew Leaf Extract: Antimicrobial Activity, Mode of Action, and Retardation of Spoilage Bacteria in Refrigerated Nile Tilapia Slices.

Phenolic compounds from cashew (Anacardium occidentale L.) leaves were extracted using ethanol with the aid of ultrasonication. Three independent variables, including ultrasound amplitude, time, and ethanol concentration, were used for response surface methodology (RSM) along with the central composite design (CCD). Under the optimized condition (70% amplitude; 40 min; 80% ethanol), the extraction yield and total phenolic contents were 24.50% and 431.16 mg GAE/g dry extract, respectively. Cashew leaf extract (CLE) had the lower minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) against Shewanella sp. than P. aeruginosa. The release of K+ and Mg2+ ions from damaged cell membranes with a coincidental decrease of TTC dehydrogenase activity were augmented when treated with CLE. In addition, scanning electron microscopic (SEM) image revealed deformations and perforation of cell walls of bacteria treated with CLE. The dominant compounds in CLE were amentoflavone, quercetin, and its glycosides. Based on microbial challenge test, the growth of P. aeruginosa and Shewanella sp. inoculated in tilapia slices were inhibited by CLE at 400 and 600 ppm within 15 days of refrigerated storage.

Bio-inspired one-dimensional based textile fabric coating for integrating high flame retardancy, antibacterial, toxic gases suppression, antiviral and reinforcement properties

Herein, a green synthesis approach has been used for development of innovative, renewable, efficient and cost-effective flame retardant, antivirus, reinforced and antibacterial coatings for textile fabrics. Hence, rennet casein as biopolymer was facilely prepared from renewable caw milk source and its solution was prepared and then, abundant halloysite nanotubes (HNTs) were uniformly dispersed with aid of ultrasonication producing new one-dimensional nanocomposite. Afterwards, the developed coatings were coated on different textile fabrics. The mass loadings of HNTs dispersed in casein solution were varied. The flammability, toxic gases suppression, reinforcement, antibacterial, and antiviral properties of the coated textile fabrics were significantly enhanced. The flame retardancy of treated textile fabrics achieved zero rate of burning (horizontal test) compared to 119 mm/min for blank cotton textile recording high-class flame-retardant textile. Additionally, the flame retardancy was corroborated from high LOI value of 35% compared to 18.5% for blank sample. Interestingly, the coated textile fabrics recorded significant inhibition of bacterial growth recording 17.6 mm of clear inhibition zone compared to zero for virgin and casein coated samples. Interestingly, the as developed coating affords more than 90% antiviral inhibition for adenovirus and herpesvirus. This is in addition to significant reinforcement of more than two-fold increase in tensile strength achieving excellent reinforcement. Interestingly, the developed coated textile fabrics achieved outstanding toxic gases suppression after combustion recording reduction in emission in CO, CO2, SO2, NOx and NO, by 97,70,85,75,75% respectively. Flame retardancy and toxic gases suppression mechanism was discussed and elucidated.

Assessment of antioxidant, antimicrobial, and anticancer activities of Sisymbrium officinale plant extract

The most efficient and safe source of medications is the natural and traditional medications which are produced from plants and herbs. In this study, Sisymbrium officinale (S. officinale) was tested to explore its total phenolic and flavonoids contents. Antioxidant, antimicrobial, and anticancer activities were assessed as well. S. officinale was bought from a local Palestinian market, air-dried, and extracted with 99% ethanol with the aid of ultrasonication. The extract was tested on three types of bacteria using well diffusion method. The anti-microbial testing included three different types of bacteria, two gram-positive bacteria, Streptococcus and Staphylococcus and E. coli as a gram-negative bacterium. Antioxidant activity of the plant extract was conducted using DPPH method, while total phenolic and flavonoids contents were performed using a well-known assay chemical method. Anticancer activity of the extract was conducted against two cancer cell lines (breast (MCF7) and colon (HCT116) cancer cell lines). Results showed that the extract is rich polyphenolic and flavonoids and has strong antioxidant activity reflected by inhibition of free radicals (DPPH) (193.7 ± 3.4). The plant extract showed also strong antimicrobial activity against both E. coli and Streptococcus bacteria with of inhibition of 10 and 14 mm respectively. The extract of this plant also showed anticancer activity (about 6%) against MCF7 (breast cancer cell line).

The effect of ultrasound on synthesis and energy storage mechanism of Ti3C2Tx MXene

Removal of aluminum (abbreviated to Al) accounts for the main step for synthesizing Ti3C2Tx MXene. To date, the synthesis of Ti3C2Tx MXene is hampered by the low removal efficiency of Al from Ti3AlC2. Ultrasound was therefore introduced to achieve efficient synthesis of Ti3C2Tx MXene by promoting the removal rate of Al from Ti3AlC2. It was found that ultrasonic aid can significantly boost the removal efficiency of Al. Additionally, distinct kinetics for the removal of Al was recognized as the advent of ultrasonic intervention: (i) the shrinking core model was used to describe the removal kinetics of Al in the case without ultrasound, whilst the shrinking particle model was capable for the case in presence of ultrasound; (ii) the activation energy for removal of Al with ultrasonic aid was 70.2 kJ/mol, indicating a chemical reaction-controlled process, whereas the corresponding value for the case without sonication was 28.1 kJ/mol, demonstrating a mixed kinetic feature of the removal process of Al. Morphological study showed that ultrasound can remove the surface-adhering reaction products and favors the formation of structures with flower-like morphology. The sample without sonication treatment exhibited typical capacitive behavior, whilst the contribution of diffusion-limited capacitance in addition to the capacitive behavior was readily observed for the sonication-treated sample. Surface chemistry study indicated the more prevalent oxidation of the sonication treated sample, which gave rise to a higher specific capacitance than those without sonication treatment.

Microcapsules of Shrimp Oil Using Kidney Bean Protein Isolate and κ-Carrageenan as Wall Materials with the Aid of Ultrasonication or High-Pressure Microfluidization: Characteristics and Oxidative Stability.

Emulsions containing shrimp oil (SO) at varying amounts were prepared in the presence of red kidney bean protein isolate (KBPI) and κ-carrageenan (KC) at a ratio of 1:0.1 (w/w). The emulsions were subjected to ultrasonication and high-pressure microfluidization to assist the encapsulation process. For each sample, ultrasonication was carried out for 15 min in continuous mode at 80% amplitude, whereas high-pressure microfluidization was operated at 7000 psi for 10 min. Ultrasonicated and microfluidized emulsions were finally spray-dried to prepare KBPI-KC-SO microcapsules. Moderate to high encapsulation efficiency (EE) ranging from 43.99 to 89.25% of SO in KPBI-KC-SO microcapsules was obtained and the microcapsules had good flowability. Particle size, PDI and zeta potential of KBPI-KC-SO microcapsules were 2.58–6.41 µm, 0.32–0.40 and −35.95–−58.77 mV, respectively. Scanning electron microscopic (SEM) images visually demonstrated that the wall material/SO ratio and the emulsification method (ultrasonication vs microfluidization) had an impact on the size, shape and surface of the KBPI-KC-SO microcapsules. Encapsulation of SO in microcapsules was validated empirically using Fourier transform infrared (FTIR) analysis. Encapsulation of SO in KBPI-KC microcapsules imparted superior protection against oxidative deterioration of SO as witnessed by the higher retention of polyunsaturated fatty acids (PUFAs) and astaxanthin when compared to unencapsulated SO during extended storage at room temperature.

Sonochemical decoration of palladium on graphene carpet for electrochemical methanol oxidation

• Decoration of palladium nanoparticles on graphene carpets (Pd/rGO) via low-frequency ultrasonication. • Investigate Pd/rGO as an electrocatalyst towards methanol oxidation. • Pd/rGO shows a higher activity of 51.68 mA cm −2 than commercial Pd/C catalyst. • Pd/rGO shows better stability not only in the initial state but also after the 3600 s. Fuel cells can be considered an effective and sustainable energy source to overcome the upcoming energy crisis. Among other fuel cells, Direct Methanol Fuel Cell (DMFC) attained great attention due to ease in storage and transportation along with the high volumetric energy density of methanol. The application of nanomaterials with unique morphologies and properties towards electrochemical methanol oxidation are being intensively studied to improve efficiency. Noble metals and their composites are generally considered the best candidates as electrode materials for methanol oxidation. In this work, a green strategy for the decoration of palladium nanoparticles on graphene carpets (Pd/rGO) has been proposed using glucose as a reducing and stabilizing agent through the aid of ultrasonication. As prepared material was properly analyzed with suitable analytical instruments. The electrochemical performance of the composite was investigated as an electrocatalyst towards methanol oxidation using Cyclic Voltammetry (CV) and Chronoamperometry (CA) techniques. A comparative study of the electrocatalytic activity towards methanol oxidation was carried out among as-prepared Pd/rGO, palladium nanoparticles (Pd NPs), and commercially available palladium on carbon (Pd/C) catalysts Among other samples, Pd/rGO shows a higher activity of 51.68 mA cm −2 during the electrooxidation of methanol than the individual and the commercial. Further, the long-term assessment also shows Pd/rGO has better stability not only in the initial state but also after the 3600 s.