•Slit divergent ultrasound enhanced the glycation reaction between SPI and lentinan.•Ultrasound assisted Maillard reaction could enhance the utilization of SPI.•The secondary structure of conjugates ...was changed by ultrasound treatment.•Emulsion prepared by SPI-lentinan conjugates had better physical stability.
Effects of a novel slit divergent ultrasound (SDU) treatment on soybean protein isolate (SPI)-lentinan conjugates via Maillard reaction was investigated. Besides, the stability of emulsions prepared by SPI and SPI-lentinan conjugates (ultrasound and un-ultrasound) as emulsifiers was compared. The results showed that ultrasonic treatment (40 min) markedly increased the degree of grafting (26.48%) by 1.91 times comparing with traditional heating method (2 h, 13.89%). In addition, structural analysis showed that the conjugates obtained by SDU treatment changed the secondary structure and had higher surface hydrophobicity and fluorescence intensity than those obtained by traditional heating method. Apart from this, SDU treatment could significantly improve the functional properties (solubility, foaming, emulsifying capacity, thermal stability, and viscosity) of conjugates. Furthermore, the emulsions prepared by the SPI-lentinan conjugates (ultrasound) as emulsifiers possessed the highest stability against environmental stresses. Taken together, SDU-assisted heating could be an excellent method to improve the functional properties of conjugates.
Developing a cost-effective, stable, and recyclable adsorbent with high adsorption capacity and rapid adsorption kinetics is highly demanded for water treatment but has been proven challenging. ...Herein, we report a one-step strategy to synthesize tough porous nanocomposite hydrogel, by introducing biochar nanoparticles and interconnected pores into a polyacrylamide hydrogel matrix as an exemplary system. The polyacrylamide hydrogel provides the overall mechanical strength to carry loads and facilitate recycling, the biochar provides adsorptive locus for high adsorption capacity, and the interconnected pores expedite solvent transport for rapid adsorption kinetics. Mechanical characterizations manifest that the porous biochar hydrogel possesses a tensile strength of 128 kPa, a stretchability of 5.9, and a toughness of 538 J m–2. Porous structure analysis reveals that the hydrogel contains an increscent specific surface area by 441% and an augmented pore volume by 279% compared to pure polyacrylamide hydrogel. Experiments pertaining to adsorption isotherms and kinetics, with methylene blue as the model adsorbate, indicate enhanced adsorption performances. The tough hydrogel also allows facile recycling and maintains mechanical robustness after five regeneration cycles. Furthermore, biocompatibility is endorsed by cytotoxicity test. The proposed method could open an ample space for designing and synthesizing tough porous nanocomposite hydrogels for water treatment.
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•A generic principle is proposed to synthesize tough porous biochar hydrogel (PBH) for water treatment.•The PBH shows enhanced adsorption capability and kinetic in dye removal.•The PBH allows facile recycling and maintains mechanical robustness after five cycles of regeneration.
Due to the imperfect development of the photosynthetic apparatus of the newborn leaves of the canopy, the photosynthesis ability is insufficient, and the photosynthesis intensity is not only related ...to the external environmental factors, but also significantly related to the internal mechanism characteristics of the leaves. Light suppression and even light destruction are likely to occur when there is too much external light. Therefore, focus on the newborn leaves of the canopy, the accurate construction of photosynthetic rate prediction model based on environmental factor analysis and fluorescence mechanism characteristic analysis has become a key problem to be solved in facility agriculture. According to the above problems, a photosynthetic rate prediction model of newborn leaves in canopy of cucumber was proposed. The multi-factorial experiment was designed to obtain the multi-slice large-sample data of photosynthetic and fluorescence of newborn leaves. The correlation analysis method was used to obtain the main environmental impact factors as model inputs, and core chlorophyll fluorescence parameters was used for auxiliary verification. The best modeling method PSO-BP neural network was used to construct the newborn leaf photosynthetic rate prediction model. The validation results show that the net photosynthetic rate under different environmental factors of cucumber canopy leaves can be accurately predicted. The coefficient of determination between the measured values and the predicted values of photosynthetic rate was 0.9947 and the root mean square error was 0.8787. Meanwhile, combined with the core fluorescence parameters to assist the verification, it was found that the fluorescence parameters can accurately characterize crop photosynthesis. Therefore, this study is of great significance for improving the precision of light environment regulation for new leaf of facility crops.
In this paper, mold simulator trials were firstly carried out to study the phenomena of the initial shell solidification of molten steel and the heat transfer across the initial shell to the ...infiltrated mold/shell slag film and mold. Second, a one-dimensional inverse heat transfer problem for solidification (1DITPS) was built to determine the temperature distribution and the heat transfer behavior through the solidifying shell from the measured shell thickness. Third, the mold wall temperature field was recovered by a 2DIHCP mathematical model from the measured in-mold wall temperatures. Finally, coupled with the measured slag film thickness and the calculations of 1DITPS and 2DIHCP, the thermal resistance and the thickness of liquid slag film in the vicinity of the meniscus were evaluated. The experiment results show that: the total mold/shell thermal resistance, the mold/slag interfacial thermal resistance, the liquid film thermal resistance, and the solid film thermal resistance is 8.0 to 14.9 × 10
−4
, 2.7 to 4.8 × 10
−4
, 1.5 to 4.6 × 10
−4
, and 3.9 to 6.8 × 10
−4
m
2
K/W, respectively. The percentage of mold/slag interfacial thermal resistance, liquid film thermal resistance, and solid film thermal resistance over the total mold/shell thermal resistance is 27.5 to 34.4, 17.2 to 34.0, and 38.5 to 48.8 pct, respectively. The ratio of radiation heat flux is around 14.1 to 51.9 pct in the liquid slag film.
The efficient CO
2
capture, separation, storage and utilization have received increasing attention to alleviate carbon emission and greenhouse effect. In this work, the first-principles calculations ...were performed to investigate the adsorption behaviors of CO
2
, H
2
, N
2
and CH
4
on the penta-BN
2
monolayer with different charge density/electric field intensity, which aims to explore the possibility of penta-BN
2
sheet as an alternative CO
2
capture material. The results show that the CO
2
is physisorbed on the neutral penta-BN
2
sheet, whereas the interactions between the CO
2
and the penta-BN
2
surface would be significantly strengthened after introducing appropriate negative charge density/electric field. Interestingly, the CO
2
adsorption/desorption processes are spontaneous, reversible and could be effortlessly controlled by introducing/removing extra electrons or external electric field into/from the penta-BN
2
nanosheet. The adsorption strength of H
2
, N
2
and CH
4
is weaker than that of CO
2
on penta-BN
2
sheet under the condition of charge/electric field. Namely, the CO
2
could be effectively captured and separated from the mixtures of H
2
, N
2
and CH
4
with the assistance of negative charge/electric field. These theoretical conclusions could provide a helpful guideline in search of materials with excellent CO
2
capture capacity.
Graphical abstract
Optimization and control of the greenhouse light environment is key to increasing crop yield and quality. However, the light saturation point impacts the efficient use of light. Therefore, the ...dynamic acquisition of the light saturation point that is influenced by changes in temperature and CO
concentration is an important challenge for the development of greenhouse light environment control system. In view of this challenge, this paper describes a light environment optimization and control model based on a crop growth model for predicting cucumber photosynthesis. The photosynthetic rate values for different photosynthetic photon flux densities (PPFD), CO
concentration, and temperature conditions provided to cucumber seedlings were obtained by using an LI-6400XT portable photosynthesis system during multi-factorial experiments. Based on the measured data, photosynthetic rate predictions were determined. Next, a support vector machine(SVM) photosynthetic rate prediction model was used to obtain the light response curve under other temperatures and CO
conditions. The light saturation point was used to establish the light environment optimization and control model and to perform model validation. The slope of the fitting straight line comparing the measured and predicted light saturation point was 0.99, the intercept was 23.46 and the coefficient of determination was 0.98. The light control model was able to perform dynamic acquisition of the light saturation point and provide a theoretical basis for the efficient and accurate control of the greenhouse light environment.
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•The solubility of PPI treated by ultrasonic-assisted pH shift could reach 99%.•Ultrasonic-assisted pH shift increased the adsorption rate and elastic modulus of PPI.•The increase of ...β-sheet contributed to the formation of a tight interfacial structure.•Ultrasonic-assisted pH shift promoted the emulsifying and foaming properties of PPI.
In order to expand the applications of plant protein in food formulations, enhancement of its functionalities is meaningful. Herein, the effects of ultrasonic (20 KHz, 400 W, 20 min)-assisted pH shift (pH 10 and 12) treatment on the structure, interfacial behaviors, as well as the emulsifying and foaming properties of perilla protein isolate (PPI) were investigated. Results showed that the solubility of PPI treated by ultrasonic-assisted pH shift (named UPPI-10/12) exceeded 90 %, which was at least 2 and 1.4 times that of untreated PPI and ultrasound-based PPI. Meanwhile, UPPI-10/12 possessed higher foamability (increasing by at least 1.2 times) and good emulsifying stability. Ultrasonic-assisted pH shift treatment decomposed large PPI aggregates into tiny particles, evident from the dynamic light scattering (DLS) and atomic force microscopy results. Besides, this approach induced a decrease in α-helix of PPI and an increase in β-sheet, which might result in the exposure of the hydrophobic group on the structural surface of PPI, thus leading to the increase of surface hydrophobicity. The smaller size and higher hydrophobicity endowed UPPI-10/12 faster adsorption rate, tighter interfacial structure, and higher elastic modulus at the air- and oil–water interfaces, evident from the cryo-SEM and interfacial dilatational rheological results. Thus, the emulsifying and foaming properties could evidently enhance. This study demonstrated that ultrasonic-assisted pH shift technique was a simple approach to effectively improve the functional performance of PPI.
The global outbreak of the monkeypox virus (MPXV) highlights the need for rapid and cost‐effective MPXV detection tools to effectively monitor and control the monkeypox disease. Herein, we ...demonstrated a portable CRISPR–Cas‐based system for naked‐eye detection of MPXV. The system harnesses the high selectivity of CRISPR–Cas12 and the isothermal nucleic acid amplification potential of recombinase polymerase amplification. It can detect both the current circulating MPXV clade and the original clades. We reached a limit of detection (LoD) of 22.4 aM (13.5 copies/µl) using a microtiter plate reader, while the visual LoD of the system is 75 aM (45 copies/µl) in a two‐step assay, which is further reduced to 25 aM (15 copies/µl) in a one‐pot system. We compared our results with quantitative polymerase chain reaction and obtained satisfactory consistency. For clinical application, we demonstrated a sensitive and precise visual detection method with attomolar sensitivity and a sample‐to‐answer time of 35 min.
A photosynthetic prediction rate model is a theoretical basis for light environmental regulation, and the existing photosynthetic rate prediction models are limited by low modeling speed and ...prediction accuracy. Therefore, this paper analyses effects of light quality on photosynthesis rate, and proposes a method based on Radial basis function (RBF) optimized by Quantum genetic algorithm (QGA) to establish photosynthetic rate prediction model. We selected "golden embryo
formula 98-1F1" cucumber seedlings as experimental material and used LI-6800 to record the photosynthetic rates under different temperatures, light intensities and light quality. Experimental data is used to train and test the proposed model. The determinant coefficient of the model between the predicted and the measured values is 0.996, the straight slope of linear fitting is 1.000, and the straight intercept of linear fitting is 0.061. Moreover, the proposed method is compared with 6 artificial intelligence algorithms. The comparison results also validate that the proposed model has the highest accuracy compared with other algorithms.
The surface quality of the continuous casting strands is closely related to the initial solidification of liquid steel in the vicinity of the mold meniscus, and thus the clear understanding of the ...behavior of molten steel initial solidification would be of great importance for the control of the quality of final slab. With the development of the mold simulator techniques, the complex interrelationship between the solidified shell surface profile, heat flux, shell thickness, mold level fluctuation, and the infiltrated slag film was well illustrated in our previous study. As the second part, this article investigated the effect of the mold oscillation frequency, stroke, and mold level fluctuation on the initial solidification of the molten steel through the conduction of five different experiments. Results suggested that in the case of the stable mold level, the oscillation marks (OMs) exhibit equally spaced horizon depressions on the shell surface, where the heat flux at the meniscus area raises rapidly during negative strip time (NST) period and the presence of each OMs on the shell surface is corresponding to a peak value of the heat flux variation rate. Otherwise, the shell surface is poorly defined by the existence of wave-type defects, such as ripples or deep depressions, and the heat flux variation is irregular during NST period. The rising of the mold level leads to the longer-pitch and deeper OMs formation; conversely, the falling of mold level introduces shorter-pitch and shallower OMs. With the increase of the mold oscillation frequency, the average value of the low-frequency heat flux at the meniscus increases; however, it decreases when the mold oscillation stroke increases. Additionally, the variation amplitude of the high-frequency temperature and the high-frequency heat flux decreases with the increase of the oscillation frequency and the reduction of the oscillation stroke.
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