Ultrasonic Conditions Research Articles

Chemical resistant silver nanowire/cellulose nanofibril flexible transparent conductive coatings

In this research, a coating method is developed to produce chemical resistant transparent conductive films (TCFs). First, cellulose nanofibers are ultrasonicated to physically untangled into thinner units. Silver nanowires (AgNWs) are then mixed with the ultrasonicated cellulose nanofibers (uCNF), which serve as a dispersion agent for stable coating fluids. After coating on a flexible substrate by a blade coating procedure, the uCNFs wrap over AgNWs to form a thin protecting layer, and the embedded AgNWs exhibit a highly percolating conductive network. As a result, the coating shows not only a low sheet resistance of 7.5 Ω/square with a great transparency of 91.5 % transmittance, but also an excellent adhesion under bending conditions. Additionally, the chemical and mechanical stability of the TCF can be further improved by cross-linking with citric acid. The ester bonding between the crosslinked uCNF rods provides a continuous hydrophobic network with a more compact structures for great mechanical stability under bending or ultrasonication conditions. Moreover, the crosslinked TCF shows high chemical tolerance and remain conductive after submerged in strong acid or basic solutions. The crosslinked TCF exhibits a high transparency and conductivity with a high figure of merit factor of 515, much better than many AgNW-based TCF, and can be used for various optoelectronic applications.

Effects of different thermoultrasonic time on quality characteristics of fishbone broth and correlation analysis on taste substances

AbstractThermoultrasonic treatment (TUT) has a superb effect on improving the quality of fishbone broth. To further investigate the effects of different thermoultrasonic time (2, 4, 6, 8, 10, and 12 min) on quality characteristics of halibut bone broth, the nutritional composition, system, and flavor traits are studied in this article. Results indicate that thermoultrasonic time is not proportional to the quality of fishbone soup, the sample has the best quality traits under the ultrasonic condition at 10 min. The particle size distribution is more concentrated (605.92 nm). Additionally, the correlation analysis on taste substances is discussed. Continuous formation of micro nanoparticles (MNPs) drives the interaction between molecules and further accumulates the main nutrients and flavor compounds through the ultrasonic process. Hence, TUT at 10 min can be effectively used as an optimization condition in the field of fishbone by‐product processing.Novelty impact statementUltrasonic time is not proportional to the quality of halibut bone soup. The soup system is more stable, thick, and milky at an ultrasonic power of 10 min. Correlation analysis among FAAs, 5′‐nucleotides, and organic acids is discussed.

Novel Approach to Synthesis of AgZnS and TiO2 Decorated on Reduced Graphene Oxide Ternary Nanocomposite for Hydrogen Evolution Effect of Enhanced Synergetic Factors.

In this work, a novel ternary nanocomposites AgZnS-TiO2-reduced graphene oxide (RGO) was successfully synthesized by a facile soft ultrasonic-reduction condition as low as 70 °C. During the ultrasound reaction, the reduction of GO and the growth of AgZnS and TiO2 crystals occurred simultaneously in conjunction with the deposition of AgZnS and TiO2 crystals onto the surface of the graphene. The synthesized nanocatalysts were characterized by XRD, SEM, TEM, EDX, Raman spectroscopy, XPS, UV–Vis DRS, photoluminescence spectrometer, and photocurrent and CV. The AgZnS-G-T was shown as catalytic HER with some synnegetic factors such as pH-universal, temperature, and ultrasonic condition. After 4 h, it was observed that AgZnS-TiO2-RGO has the highest efficiency of photocatalytic activity through hydrogen production by water splitting, which achieved the highest hydrogen evolution rate of 930.45 μmol/g at buffer solution (pH = 5), which was superior to AgZnS-G (790.1 µmole/g) and AgZnS (701.2 µmole/g). Such a significant hydrogen evolution amount far exceeded that of undoped TiO2 and RGO. The H2 evolution amounts increased significantly at ultrasonic irradiation power of 80 MHz. AgZnS-G-T demonstrates the higher H2 evolution amounts of 985 µmole/g at 80 MHz. Its photocatalytic hydrogen-evolution activity remained at a high level over four cycles (16 h) nanoparticle.

Kurutulmuş Domateslerin Ultrasonik Rehidrasyon Koşullarının Optimizasyonu

In this study, it was aimed to optimize the ultrasonic rehydration conditions of dried tomatoes.
 Rehydration conditions were optimized by Response Surface Method (RSM). The optimization of ultrasonic (37 kHz) rehydration conditions were performed with independent variables at different temperatures (20-80°C), time (2-60 min) and water ratios (1/50-1/100 g/g water), and rehydration ability, color a* (redness) and texture values were selected as responses (dependent variable). The estimated and experimental analysis results were compared in the selection of the optimum rehydration condition. As a result, it was determined that ultrasonic rehydration at 58°C/54 min/72 ml water conditions could be used as the optimum point. At the selected optimum point, the rehydration ability, color a* value and texture values were determined as 2.82±0.16, 13.09 ±1.63 and 0.46±0.13 N, respectively. These results are seen as proof that ultrasound application can be used in the rehydration of dried tomatoes.

초음파 압력 펄스에 의한 미세기포와 세포 간의 상호작용에 대한 수치적 연구

The collapse of microbubbles using ultrasonic pressure pulses is accompanied by strong shock waves and jets. This phenomenon is an important topic applied to various environmental and medical fields such as surface cleaning, algae removal, cell poration, and drug delivery. However, a numerical model that can capture the strong bubble collapse, liquid jet, and associated deformation of a cell is lacking in the literature. In this work, numerical simulations are performed for the interaction between the spherical bubble and cell under an ultrasonic pulse condition including the effects of bubble collapsing jet and cell deformation. The cell is treated as a compressible liquid and two distance level-set functions are used for the bubble and cell interfaces. The conservation equations of mass and momentum are solved for compressible two-phase flows. The effects of acoustic amplitude and frequency and initial bubble-cell distance are investigated. The results show that cell deformation increases with increasing acoustic amplitude or decreasing frequency, and the distance between the bubble and cell is observed as an important parameter for cell deformation under the same ultrasound conditions. The present work can contribute to a safer and more efficient use of ultrasound in environmental and medical applications.

Ultrasonic assisted stretching approach toward aligned CNT for high strength and conductive nanocomposite

Carbon nanotubes (CNTs) reinforced polymeric nanocomposite is one of the most promising candidates for the future lightweight and multifunctional material. Two prerequisites for the development of high-performance nanocomposites are the strong interfacial interaction and high orientation of CNTs in the matrix, which are extremely challenging due to the fact that CNTs tend to mostly agglomerate into bundles. Herein, we demonstrated an ultrasonic assisted stretching strategy to enhance interfacial interaction and the orientation of CNTs in composites, which was attributed to the de-bundling effect of CNTs generated by ultrasonic cavitation and the inter-tube sliding effect assisted by resin lubrication during stretching processing. Under the optimal ultrasonic processing conditions, the strength, modulus, toughness and electrical conductivity of aligned nanocomposites can be improved by up to 43.5%, 68.8%, 42.5% and 144.1%, respectively, compared with those without ultrasonic treatment. This ultrasonic assisted stretching strategy could be easily extended to develop composites reinforced by other discontinuous fillers, such as boron nitride nanotubes, carbon nanofibers, and many whiskers.

Kinetic and mechanistic study of ultrasonic inactivation of Kunitz (KTI) and Bowman-Birk (BBI) inhibitors in relation to process-relevant parameters

In this study, quantitative monitoring of low-frequency (20 kHz) and high-frequency (355 kHz) ultrasound-induced inactivation of Kunitz (KTI) and Bowman-Birk inhibitor (BBI) using RP-HPLC was achieved, and its consistency with a traditional TI activity assay was verified. The effect of TI concentration, ultrasonic frequency, power density and pH on inactivation kinetics of KTI and BBI was explored. Results showed that the pseudo-first-order kinetic rate constants of KTI and BBI were decreased by over 60% when the initial TI concentration was increased from 100 mg/L to 1000 mg/L. Also, the amounts of inactivated KTI and BBI were increased by around 4-fold at the higher TI concentration of 1000 mg/L (20 kHz, 1.71 W/mL and pH 4). The colloidal environment and ultrasonic conditions influenced the secondary and tertiary structure and particle size of TIs in LF-induced inactivation. In comparison, the abovementioned conditions affected the oxidation of methionine and the conformational change of TIs in HF-induced inactivation.

One-pot preparation of pectin encapsulated Cu2O nanoparticles under ultrasound condition: Investigation of its catalytic, cytotoxicity, antioxidant, and anti-colorectal cancer properties

• The nanocomposite exhibited excellent cytotoxicity against colorectal carcinoma (CL40, SW1417, and CW2) cell lines. • IC 50 values of the nanocomposite were found at 60, 54 and 53 µg/mL against CL40, SW1417, and CW2 cell lines respectively. • Structural features of the material were assessed over several advanced techniques like FT-IR, UV–Vis spectroscopy, SEM, TEM, EDX and XRD. A mild approach for synthesis of Cu 2 O nanoparticles by using pectin were described through a simple and ‘green’ way under ultrasonic conditions. The polar functional groups on the pectin (OH) facilitate the capping and stabilization of Cu 2 O nanoparticles. Structural features of the Cu 2 O NPs/pectin were assessed over several advanced techniques like UV–Vis spectroscopy, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), energy dispersive X-ray analysis (EDX) elemental mapping, transmission electron microscopy (TEM), X-ray diffraction analysis (XRD), and inductively coupled plasma-atomic emission spectrometry (ICP-AES) analysis. It was catalytically explored in reducing an organic dye (Methylene blue-MB) in the presence of NaBH 4 at mild conditions. The Cu 2 O NPs/pectin was recycled 9 times keeping consistency in its reactivity. IC 50 values of the nanocomposite were found at 60, 54 and 53 µg/mL against CL40, SW1417, and CW2 cell lines respectively and accordingly, CW2 afforded the best carcinoma activity. The nanocomposite exhibited excellent cytotoxicity against colorectal carcinoma (CL40, SW1417, and CW2) cell lines without affecting the normal (HUVEC) cell line.

Simultaneous determination of 40 plant growth regulators, fungicides, insecticides, and antibiotics in bean sprouts by QuEChERS-high performance liquid chromatography-tandem mass spectrometry

研究从豆芽质量安全监管的实际需求出发,建立了QuEChERS-高效液相色谱-串联质谱同时测定豆芽中植物生长调节剂、杀菌剂、杀虫剂和抗生素类等40种药物残留的方法。首先通过参数优化确定最佳质谱条件,然后比较不同提取溶剂(甲醇、乙腈、0.1%氨水乙腈、1%乙酸乙腈)、提取方法(超声、振荡)以及乙二胺-N-丙基硅烷化硅胶(PSA)、C18净化剂添加量时40种药物的回收率,确定最优前处理过程。样品用10 mL 1%乙酸乙腈提取两次,超声波辅助提取,100 mg C18为净化剂。选用Waters ACQUITY UPLC BEH C18色谱柱(100 mm×2.1 mm, 1.7 μm)进行分离,甲醇和0.01%甲酸水为流动相梯度洗脱,多反应监测(MRM)模式进行质谱监测,基质匹配外标法定量。结果表明,40种药物可在15 min内完成色谱分离,在2~200 μg/L的线性范围内均呈现出良好的线性关系,相关系数(r2)均大于0.99,检出限(LOD)和定量限(LOQ)分别为0.1~3 μg/kg和0.3~9 μg/kg。以阴性豆芽为基质,分别在5、10、50 μg/kg 3个水平下进行加标回收试验,40种药物的平均回收率为78.5%~115.3%,相对标准偏差(RSD)为1.3%~9.7%(n=6)。将该方法用于分析邯郸本地豆芽中40种药物的污染状况,结果显示4-氯苯氧乙酸、6-苄基腺嘌呤、多菌灵、2,4-二氯苯氧乙酸(2,4-D)、赤霉素和恩诺沙星检出率较高,分别为28.6%、19.0%、9.5%、9.5%、4.8%和4.8%,含量范围为37.5~352.4、32.4~273.1、28.8~38.7、16.1~20.2、19.9和13.6 μg/kg。研究建立的方法简单、快速,灵敏度高,适用于大批量豆芽中40种药物的快速准确测定。

Characterization of cavitation under ultrasonic horn tip – Proposition of an acoustic cavitation parameter

Acoustic cavitation, generated by a piezo-driven transducer, is a commonly used technique in a variety of processes, from homogenization, emulsification, and intensification of chemical reactions to surface cleaning and wastewater treatment. An ultrasonic horn, the most commonly used acoustic cavitation device, creates unique cavitation conditions under the horn tip that depend on various parameters such as the tip diameter, the driving frequency of the horn, its amplitude, and fluid properties. Unlike for hydrodynamic cavitation, the scaling laws for acoustic cavitation are poorly understood. Empirical relationships between cavitation dynamics, ultrasonic horn operating conditions, and fluid properties were found through systematic characterization of cavitation under the tip. Experiments were conducted in distilled water with various sodium chloride salt concentrations under different horn amplitudes, tip geometries, and ambient pressures. Cavitation characteristics were monitored by high-speed (200,000 fps) imaging, and numerous relations were found between operating conditions and cavitation dynamics. The compared results are discussed along with a proposal of a novel acoustic cavitation parameter and its relationship to the size of the cavitation cloud under the horn tip. Similar to the classical hydrodynamic cavitation number, the authors propose for the first time an acoustic cavitation parameter based on experimental results.

Silica nanostructures against fungal growth: design and preparation of antifungal cotton fabrics

The preparation of antifungal-functionalized silica nanoparticles by covalent attachment of several silylated derivatives based on the topical antifungal agent Micozanole is described. Grafting and co-condensation procedures are used to obtain mesoporous or dense nanoparticles. Cotton fabrics have been coated with these antifungal-functionalized silica nanoparticles under ultrasonic conditions. The characterization of the functionalized nanoparticles and coated cotton fabrics is performed by microscopic and spectroscopic techniques. The antifungal activity of all the modified cotton textiles is tested against Trichophyton mentagrophytes CECT 2783, Aspergillus brasiliensis CECT 2091, Penicillium chrysogenum CECT 2307 and Candida albicans CECT 1001, resulting to be highly dependent on the microorganism. Remarkably, all of the modified fabrics are active against Candida albicans and Trichophyton mentagrophytes, with up to 75 and 90% effectiveness, respectively. High expectations arise for topical cutaneous applications in wound dressings (bandages, gauzes, strips).Graphical abstract

Experimental Investigations on the Effect of Ultrasonic Field in External Pool Boiling Under Various Operating Pressures

Abstract The augmentation of boiling heat transfer has been a dynamic domain of research for the past several decades due to a wide range of energy intensive applications and, in line, many active and passive methods have been developed. The present study discusses the effect of ultrasonic field of 31 kHz and 40 kHz on the saturated pool boiling of R141b over plain Cu surface at different operating pressures. It was found that the ultrasonic field is more effective at higher operating pressures. The surface superheat reduced by a maximum value of 2.6 °C with the application of 31 kHz ultrasonic field in comparison to the pool boiling without ultrasonic field application for +30 kPa(g) operating pressure at lower heat flux level of 113 kW/m2. The maximum augmentation in heat transfer coefficient was calculated as 37.1% and 11.4% for frequency of 31 kHz and 40 kHz, respectively, with respect to the no ultrasonic field condition at +30 kPa(g) for lower heat flux level of 113 kW/m2. The Nusselt number was found to be increasing in the sub-atmospheric as well as the pressurized operating pressure range. In comparison to the boiling without application of ultrasonic field, the maximum improvement in Nusselt number was noted as 25.3% at 31 kHz frequency of ultrasonic field and +30 kPa(g) operating conditions. This study suggests the use of lower frequency range of ultrasonic field in the presence of higher operating pressures for higher augmentation in saturated pool boiling.

An Ultrasound Application for TiO2 Photocatalytic Degradation of Methyl Orange

Nanometer TiO2 photocatalysts were prepared by the sol–gel method. The catalysts were characterized by X-ray diffraction, Fourier-transform infrared spectroscopy, ultraviolet-visible spectroscopy, and other techniques. Methyl orange solution was used for the degradation of the organic material and ultrasonic technology was used to determine the photocatalytic performance of the catalysts. The results show that the photocatalytic performance of the Ni-N-TiO2 is clearly improved under ultrasonic conditions. The TiO2 photocatalytic degradation effect is optimal at a catalyst concentration of 0.3 g/L, an initial concentration of the organic matter of 0.03 mmol/L, a nickel-doping amount of 2 mol %, and a nitrogen-doping amount of 15 mol %. The use of ultrasound technology in combination with photocatalysis has a positive effect and results in a TiO2 degradation rate of methyl orange of 95 % after 3 h.

A novel micellar system of hybrid deep eutectic solvents for extracting coumarins from herbal medicines: As a case of Suhuang antitussive capsule

Green solvents were emerged in recent years as potential extract-solvents to enhance the extract-efficiency of natural products. In this study, we reported a novel green extract-system, one of hybrid deep eutectic solvents (HDESs), which could simultaneously efficiently extract active ingredients with different polarities from herbal medicines. Initially, quantitative analyses of 14 coumarins in Suhuang antitussive capsule (SH) were performed by ultra-performance liquid chromatography coupled with triple quadrupole tandem mass spectrometry (UPLC-QqQ-MS/MS) under the multiple reaction monitoring (MRM) mode. After systematically optimizing the composition of HDESs, the composition of DL-menthol, decanoic acid, and 1-tetradecanol at a molar ratio of 6:0.5:1.5 exhibited the highest extract yields for target coumarins in SH. Then, response surface methodology (RSM) was employed to optimize the ultrasonic extraction conditions of this HDESs. The results showed that under the conditions of liquid to solid ratio of 496 mL/g, extract time of 30 min and water content of 35 %, the highest yield of total coumarins was obtained, and the extract efficiency was increased by 53.9 % compared with conventional organic solvents. Additionally, transmission electron microscopy (TEM) image showed the formation of HDESs-water micellar system during the ultrasonic-assisted extraction, which may promote the mass transfer process and improve the yield of target coumarins. This new ternary HDESs system could provide a green and effective extract technology for natural compounds with different polarities from complex plant materials.

Comparison between the use of polyether ether ketone and stainless steel columns for ultrasonic-assisted extraction under various ultrasonic conditions

The ultrasound-assisted extraction (UAE) was conducted using the stainless steel (SS) and polyether ether ketone (PEEK) columns and analyzed with high-performance liquid chromatography (HPLC) to understand the mechanism of ultrasound-assisted chromatography (UAC). Empty SS and PEEK columns were used to extract dyes from a fabric under identical conditions with several parameters including the initial ultrasonic bath temperatures (30 °C and 40 °C), ultrasound power intensities (0, 20, 40, 60, 80, and 100 %), ultrasound operation modes (normal and sweep), and ultrasound frequencies (25 kHz, 40 kHz, and 132 kHz) to compare their extraction capabilities. After 30 min of extraction, the amount of extract was determined by HPLC. The PEEK material was significantly affected by ultrasonic radiation compared to the SS material, especially at a higher temperature (40 °C), power intensity (100 %), and frequency (132 kHz) with sweep mode. At a maximum power density of 45 W/L, the extraction effectiveness ratio of PEEK to SS was in the range of 1.8 - 3.9 depending on the specific frequency, initial temperature, and with or without temperature control. The most optimal ultrasound frequencies, in terms of enhancing extraction effectiveness, are in the order of 132 kHz, 40 kHz, and 25 kHz. Unlike the SS material, the PEEK material was more affected by temperature and acoustic effects under identical conditions, especially at 132 kHz ultrasound frequency. In contrast, at lower frequencies of 40 kHz and 25 kHz, no significant differences in the acoustic effects were observed between the PEEK and SS materials. The findings of this study contribute to elucidating the roles of column materials in UAE and UAC.

Effect of Ultrasonic Degassing on Mg-Ca Binary Alloy by Ultrasonic Treatment

The effect of ultrasonic treatment parameters, including ultrasonic treatment duration, frequency resonance, and treatment temperature, on the degassing of Mg-3.03Ca alloys was investigated. The results indicated that the optimum degassing efficiency could be obtained under the ultrasonic resonant condition. When applying ultrasonic treatment for 90 s with 150 W at 700 °C, the minimum hydrogen content and the highest degassing efficiency are obtained, respectively (42.8 cm3/100 g and 27.5%). The ultrasonic treatment can remove the gas from the melt and refine the microstructures. Finally, the mechanism of ultrasonic degassing and refinement was analyzed.

Doping of W Ions to Modulate the Polarization Intensity of Bi2WO6 for Efficient Piezoelectric–Photoelechochemical Water Splitting

The built-in electric field induced by piezoelectric polarization is an important method to effectively improve the inefficient charge transport of photoelectrochemical (PEC) water splitting. Here, we introduce a certain amount of W5+ into Bi2WO6 crystal to modulate its piezoelectric polarization performance, thus improving its piezoelectric internal electric field to drive the separation of carriers to improve the piezoelectric photoelectrochemical (piezo-PEC) water splitting. The doping of W5+ ion widens the visible light response of the sample on the one hand, and increases the free charge density in Bi2WO6 nanosheets on the other hand, thereby improving the charge transfer efficiency. The Bi2WO6-2 sample exhibits the best photochemical properties, and the photocurrent density was 0.126 mA/cm2 at 1.23 V vs RHE. In addition, under ultrasonic conditions, the current of the Bi2WO6-2 photoelectrode was enhanced to 0.181 mA/cm2 at 1.23 V vs RHE. The effect of ion doping on piezo-PEC performance was further explained by comparing the PEC performance of the samples before and after the introduction of the piezoelectric built-in electric field. This work suggests future uses for Bi2WO6 piezo-PEC water splitting.

Process study of ceramic membrane-coupled mixed-cell fermentation for the production of adenine

In order to solve the problems of high complexity, many by-products, high pollution and difficult extraction of the existing adenine production process, in this study, ceramic membrane-coupled mixed cell fermentation was used to produce adenine while reducing the synthesis of by-products and simplifying the production process of adenine. Nucleoside hydrolase (encoded by the rihC gene) was used to produce adenine by coordinated fermentation with the adenosine-producing bacterium Bacillus Subtilis XGL. The adenosine hydrolase (AdHy)-expressing strain Escherichia coli BL21-AdHy was successfully employed and the highest activity of the crude enzyme solution was found by orthogonal experiments at 170 W power, 42% duty cycle, and 8 min of sonication. The highest AdHy activity was found after 18 h of induction incubation. E. coli BL21-AdHy was induced for 18 h and sonicated under the above ultrasonic conditions and the resulting crude enzyme solution was used for co-fermentation of the strain and enzyme. Moreover, 15% (v/v) of the AdHy crude enzyme solution was added to fermentation of B. subtilis XGL after 35 h. Finally, the whole fermentation system was dialyzed using coupled ceramic membranes for 45 and 75 h, followed by the addition of fresh medium. In contrast, the AdHy crude enzyme solution was added after 35, 65, and 90 h of B. subtilis fermentation, with three additions of 15, 15, and 10% of the B. subtilis XGL fermentation system. The process was validated in a 5 L fermenter and 14 ± 0.25 g/L of adenine was obtained, with no accumulation of adenosine and d-ribose as by-products. The enzymatic activity of the AdHy crude solution treated with ultrasound was greatly improved. It also reduced the cellular activity of E. coli BL21-AdHy and reduced effects on bacterial co-fermentation. Membrane-coupled dialysis solved the problem of decreased yield due to poor bacterial survival and decreased viability, and eliminated inhibition of the product synthesis pathway by adenosine. The batch addition of crude enzyme broth allowed the continuous conversion of adenosine to adenine. This production method provides the highest yield of biologically produced adenine reported to date, reduces the cost of adenine production, and has positive implications for the industrial production of adenine by fermentation. And it provides a reference for producing other high-value-added products made by fermentation.

Rapid determination of nitrofuran metabolites residues in honey by ultrasonic assisted derivatization - QuEChERS - high performance liquid chromatography / tandem mass spectrometry

In this study, a method of ultrasonic assisted derivatization combined with improved QuEChERS scheme and high performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS) was developed for the analysis of nitrofuran metabolite residues in honey samples. The optimized conditions such as ultrasonic assisted derivatization conditions, extraction methods and purification materials quantitatively obtained by matrix standard curve external standard method had finally been proved to be effective in the determination of nitrofuran metabolite residues in honey samples. In order to make the results more accurate, the matrix matched standard for isotope-labeled internal standard method was used for methodological verification. The concentration of all target substances ranged from were 0.25–20 ng/mL, with good linearity, and the correlation coefficient were 0.9999. The LOD and LOQ of the target analyte were 0.15 and 0.5 μg/kg respectively. The average recoveries of the three standards were between 1.89 % and 107.9 %. The recoveries of inter-day and intra-day tests were 96.0–100.2 % and 93.2–98.7 % respectively. The precisions of inter-day(n = 6) and intra-day(n = 6) analysis were 3.56–5.29 % and 3.09–5.13 % respectively. 85 honey samples obtained from the market were analyzed by our optimized method, of which 4 SEM and 1 AOZ were detected in 5 samples.

Ultrasonic-assisted enhancement of lithium-oxygen battery

Lithium-oxygen batteries have attracted much attention due to their high theoretical specific capacity, but their high overpotential and poor cyclic stability limit further development. These are usually closely related to the reversible reactions of the formation and decomposition of the discharge product Li2O2. This study presents the feasibility of ultrasonic-assisted enhancement of lithium-oxygen battery performance. Under the application of ultrasonic charging with 5:5 duty cycle and 675 W power, the rapid upward trend of charging voltage can be effectively suppressed, and the original overpotential of the lithium-oxygen battery can be reduced by 25.9%. In addition, at a limited specific capacity of 400 mAh g−1 and a current density of 800 mA g−1, when applying ultrasonic charging process with above ultrasonic condition every 20 cycles, the cycle life of lithium-oxygen battery with Co3O4 as the positive electrode can reach 321 cycles. Ultrasonic charging has positive effects on suppressing concentration polarization, enhancing mass transfer, and improving oxygen evolution reaction kinetics. It can effectively promote the rapid decomposition of the discharge product Li2O2, reduce the overpotential, and improve the battery cycle performance and stability.