•Ultrasonication was applied to the thawing process of bighead carp.•Differences of thawing methods on quality of slow/fast frozen bighead carp were compared.•Shorten thawing time by ultrasound was ...observed.•Fast frozen samples lost massive water after water immersion or ultrasonic thawing.•Freezing-thawing cycles did not affect the primary protein structure of fish samples.
Effects of ultrasound-assisted thawing (UAT), air thawing (AT) and water immersion thawing (WIT) on the quality of slow freezing (SF)/fast freezing (FF) bighead carp (Aristichthys nobilis) fillets were investigated. The thawing time of AT, WIT and UAT were 138, 30 and 12 min, respectively, indicating that UAT improved the thawing efficiency. UAT maintained the color and pH, and inhibited the lipid oxidation of SF/FF samples. For SF samples, thawing methods did not affect water retention and muscle structure. However, massive water loss and muscle destruction were observed in FF-WIT and FF-UAT samples. The AT did not produce any structural muscle damage; instead, it maintained the water retention in FF samples and prevented the FF fish fillets from massive water loss. No significant difference in the primary protein structure was observed among all samples. UAT can be an alternative strategy to the traditional thawing of SF fish fillets.
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•The antibacterial effect of US was in a time- and intensity-dependent manner.•US remarkably increased the sensitivity of E. coli cells to TEON.•US significantly increased the outer ...and inner membrane permeability.•US resulted in membrane fluidity reduction and membrane depolarization.•US caused conformational and compositional changes in some membrane components.
This study was aimed at providing new insights on the response of bacterial cell membranes to ultrasound exposure. Escherichia coli (E. coli) O157:H7 cells were exposed to different ultrasound treatments (power intensities of 64, 191, 372, and 573 W/cm2, frequency of 20 kHz, pulsed mode of 2 sec: 2 sec) and the dynamic changes in cell viability within 27 min were assessed. With an increase in ultrasonic intensity and prolonged duration, a 0.76–3.52 log CFU/mL reduction in E. coli populations was attained. The alterations in the sensitivity of ultrasound-treated cells to antimicrobial compounds were evaluated by exposure to thyme essential oil nanoemulsion (TEON). The treatment reduced the E. coli population by 2.16–7.10 log CFU/mL, indicating the effects of ultrasonic field on facilitating the antibacterial efficacy of TEON. Ultrasonic-treated E. coli cells also displayed remarkable morphological and ultrastructural damages with destroyed membrane integrity and misshaped cell structures, which was observed by electron microscopy analysis. Significant increase in outer and inner membrane permeability, along with the cytoplasmic leakage and membrane depolarization were assessed utilizing spectrophotometry. For the first time, significant reduction in the membrane fluidity in response to ultrasound exposure were investigated. Additional efforts in exploring the effect of ultrasonic field on some bacterial membrane compositions were performed with infrared spectroscopy. In this study, multiple lines of evidence effectively served to elucidate the alterations on cellular membrane structure and property during exposure to sonication that could extend our understanding of the antimicrobial molecular mechanisms of ultrasound.
In designing organic semiconductors for organic devices, halogenation is a very popular strategy for tuning the electronic properties and packing arrangement in the solid state. Herein, we report the ...synthesis and characterization of halogenated dibenzoa,jperylene (DBP) with triethylsilyl (TES)-ethynyl substituents at the 8- and 16-positions (TES-DBP). The resulting compounds are characterized by optical, electrochemical, crystallographic, and computational studies to clarify the effect of halogenation on the optoelectronic properties and charge-carrier transport. It is found that the halogen atoms, the degree of halogenation, and their positional locations can alter the electronic properties and crystal packing of the compounds. In contrast to fluorinated TES-DBP, the chlorinated counterpart has red-shifted maximum absorption and lower electron affinity owing to the electron delocalization between DBP core and the unoccupied 3d orbitals of Cl atom. Organic field-effect transistor measurements demonstrate that TES-2ClDBP shows a hole mobility of 0.25 cm2 V–1 s–1, which is higher than TES-2FDBP and TES-DBP. On the other hand, TES-4ClDBP exhibits ambipolar transport characteristics with electron and hole mobilities up to 0.02 and 0.07 cm2 V–1 s–1, respectively.
This study evaluated the inactivation effect of ultrasonic treatment combined with acidic electrolyzed water (AEW) on
Bacillus cereus
spores. AEW treatment reduced the spores by 1.05–1.37 log CFU/mL ...while the sporicidal effect of ultrasound was minor. More strikingly, simultaneous ultrasonic and AEW treatments for 30 min led to 2.29 log CFU/mL reduction and thus, considered a synergistic effect. Flow cytometry combined with SYTO/PI staining analysis revealed that ultrasound hydrolyzed the cortex while the AEW partially damaged the integrity of the inner membrane. Scanning and transmission electron microscopies were used to characterize the ultrastructural changes. The detachment of the exosporium induced by ultrasound was the most apparent difference compared with the control group, and the electron density of spores appeared to be heterogeneous after treatment with AEW. These results indicated that combining ultrasound with AEW is a promising decontamination technology with potential uses in the food industry and environmental remediation.
Clanis bilineata Walker (Lepidoptera: Sphingidae), a burgeoning edible insect, is experiencing rising demand in China and other regions. Despite this interest, larval production is currently ...constrained by the limitations of artificial production technologies, particularly the selection of optimal host plants. This study rigorously evaluated the performance of C . bilineatha larvae on four main host plants: round-leaf soybean, pointed-leaf soybean, black locust, and kudzu. Preference tests demonstrated that the larvae were most attracted to black locust (34.76 ± 4.65%), with subsequent preferences for kudzu (25.00 ± 6.12%), round-leaf soybean (23.17 ± 2.79%), and pointed-leaf soybean (14.02 ± 4.74%). No significant preference differences were noted between round-leaf soybean and either black locust or kudzu. In feeding assays, the larvae exhibited a marked preference for round-leaf soybean (37.36 ± 0.81 g, total feeding amount for larvae), followed by kudzu (37.26 ± 0.82 g), pointed-leaf soybean (35.38 ± 1.31 g), and black locust (28.53 ± 0.81 g). When the larvae were fed on round-leaf soybean, they exhibited significantly higher survival rate (39.33 ± 0.90%), body weight (9.75 ± 0.07 g), total biomass (383.43 ± 7.35 g), pupation rate (87.78 ± 1.73%), and egg production (189.80 ± 1.06 eggs/female) compared to other hosts. These findings uncovered that round-leaf soybean significantly enhances larval performance, suggesting its potential for improving C . bilineata larval production and sustainability in cultivation systems.
The spent ternary lithium-ion batteries were utilized as the precursors to prepare Sm–Mn and Sm–Co perovskite oxides (SmMnO
3
-spent ternary lithium-ion battery STLIB and SmCoO
3
-STLIB) for the ...first time. Their catalytic activities were evaluated by catalytic oxidation of propylene glycol methyl ether. Compared with that of the catalysts synthesized by analytical reagents, the catalytic activities of SmMnO
3
-STLIB and SmCoO
3
-STLIB had been significantly enhanced. The analysis of X-ray photoelectron spectroscopy (XPS) showed that the molar ratios of Mn
4+
/Mn
3+
and O
ads
/O
latt
of SmMnO
3
-STLIB were higher than that of pure SmMnO
3
and the Co
3+
/Co
2+
ratios of SmCoO
3
-STLIB was much larger than that of pure SmCoO
3
. The hydrogen temperature-programmed reduction (H
2
-TPR) and N
2
adsorption-desorption tests determined that the reducibilities and specific surface areas of SmMnO
3
-STLIB and SmCoO
3
-STLIB were also superior to pure catalysts. Ultimately, the by-products of the catalytic oxidation of propylene glycol methyl ether over SmMnO
3
-STLIB were also detected by gas chromatography–mass spectrometry (GC-MS). This work will provide a demonstration for the resource utilization of spent lithium ions batteries and the analysis of the increased activity obtained by using spent lithium ions batteries as the precursors to prepare catalysts.
•Vegetation increased the Manning roughness coefficient and Darcy–Weisbach friction factor in the upstream area.•Vegetation can increase runoff shear stress of upstream area at small inflow ...discharge.•The influence of vegetation with clustered stems on roughness and runoff velocity was greater than that of vegetation with branched stems.•Vegetation treatments reduced the gully headcut soil loss by 31 to 81%.•The soil loss rate was positively correlated with runoff kinetic energy.
Vegetation plays an important role in gully headcut erosion processes. However, it is still unclear how vegetation in the upstream area affects gully headcut erosion processes by changing the hydraulics. A series of in situ inflow scouring experiments were conducted on bare land plots and vegetation plots (including the upstream area, headwall, and gully bed) planted with Bothriochloa ischaemum (BI), Agropyron cristatum (AC), and Medicago sativa (MS) with clustered stems and Artemisia gmelinii (AG) with erect stems to investigate the influence of vegetation on the hydrodynamic parameters involved in gully headcut erosion processes. The results showed that, compared with bare land, vegetation increased the Manning roughness coefficient (n) and Darcy–Weisbach friction factor (f) in the upstream area by 0.2–2.5 times and 0.9–9.6 times, respectively, but reduced the runoff velocity in the upstream area and gully brink. However, the jet flow velocity at entry into the plunge pool increased rapidly after passing through the gully head. The influence of vegetation with clustered stems on roughness and runoff velocity was greater than that of vegetation with branched stems. At 3.6 m3/h inflow discharge, vegetation can increase the runoff shear stress of the upstream area. The energy consumption of the gully head, upstream area, and gully bed accounted for 74 to 76 %, 19 to 21 %, and 4 to 7 % of the total energy consumption, respectively. The four vegetation treatments reduced the gully headcut soil loss by 31 to 81 %, among which MS exhibited the highest reduction. The soil loss rate was positively correlated with the jet flow velocity and its kinetic energy, and the correlation was the best (R2 of 0.934 and 0.935, respectively, P < 0.01), presenting a logarithmic trend. These results are helpful to deepen the understanding of the roles of vegetation in regulating runoff hydraulic action during gully headcut erosion.
Mn3O4-Fe2O3 composite catalysts are in-situ synthesized via advanced oxidation followed by modifying with hydrochloric acid to improve the catalytic toluene oxidation performance. Mn3O4-Fe2O3 ...modified with 1.0 M HCl (A-1.0) exhibited best activity of toluene oxidation. The temperature of 50% toluene conversion is 245 °C and the temperature of 90% conversion is 279 °C. There are much more abundant surface lattice oxygen species and higher amount of high valence manganese and iron ions on A-1.0 catalyst, which are beneficial for improving catalytic activity. In-situ DRIFTs indicated that benzaldehyde and benzoic acid are main intermediate products on A-1.0 catalyst during toluene oxidation.
•Mn3O4-Fe2O3 catalyst is in-situ synthesized via advanced oxidation using K2FeO4 and MnSO4.•Acid-etching modified Mn3O4-Fe2O3 with different concentration of HCl showed improving catalytic performance for toluene oxidation.•Mn3O4-Fe2O3 modified with 1.0 M HCl etching exhibited the best activity of toluene oxidation.•In-situ DRIFTs result indicated that benzaldehyde and benzoic acid were main intermediate products during toluene oxidation.
•The jet flow and on-wall flow of gully head were separated by a simulated experiment.•The 77.7%-84.3% of flow volume upstream gully heads is converted to jet flow.•The ratio of soil loss due to jet ...flow, on-wall flow and their interaction is 4.6:3:1.•The on-wall erosion can weaken the evolution of plunge pool morphology.•Energy consumption of jet flow had the strongest effect on plunge pool morphology.
Gully headcut erosion is recognized as the primary process of gully erosion and is the main contributor to sediment yield of gully erosion. However, the proportion of jet flow and on-wall flow induced by headcut and its effects on soil loss and plunge pool morphology are still unclear. A simulated flow-scouring experiment was conducted to explore the proportion of jet flow and on-wall flow and their contributions to soil loss and the effect of on-wall flow erosion on plunge pool morphology under different flow discharge (q0 = 3.0–7.2 m3 h−1) and headwall height (H0 = 0.3–1.2 m) conditions. Our results showed that jet flow and on-wall flow accounted 15.7% − 22.6% and 77.4% − 84.3% of total flow volume upstream headcut, respectively. Jet flow, on-wall flow and their interaction contributed 53.5%, 34.9% and 11.6% of total soil loss amount, respectively. Furthermore, H0 exhibited greater effect on soil loss caused by jet flow and its interaction with on-wall flow, but the soil loss caused by on-wall was mainly controlled by q0. The width and depth of plunge pool logarithmically increased with scouring time, and the q0 and H0 significantly affected the development of plunge pool morphology. On-wall flow reduced plunge pool depth by 27.8%–71.4%, and it weakened plunge pool width by 24.3%−57.3% only under H0 of 0.3–0.9 m, but for H0 of 1.2 m and q0 of >4.8 m3 h−1, it improved the plunge pool width by 7.5%. The energy consumption of jet flow showed the closest relationship with plunge pool morphology. The concentrated flow upstream gully head exhibited the stronger effect on plunge pool morphology than H0. This study is helpful to deepen the understanding of gully erosion mechanism and provide scientific reference for the design of gully erosion prevention and control measures.
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