sp. LH 10-3-1 was newly isolated from the alkali lake water samples collected in Inner Mongolia. In this study, a gene coding for D-lactate dehydrogenase from the strain LH 10-3-1 (SaLDH) was cloned and characterized. The recombinant enzyme was a tetramer with a native molecular mass of 146.2 kDa. The optimal conditions for SaLDH to reduce pyruvate and oxidize D-lactic acid were pH 8.0 and pH 5.0, at 25 °C. Cu2+ and Ca2+ slightly promoted the oxidation and reduction activities of SaLDH, respectively. To improve the stability of SaLDH, the enzyme was immobilized on Cu3(PO4)2-based inorganic hybrid nanoflowers. The results showed that the reduction activity of the hybrid nanoflowers disappeared, and the optimum temperature, specific activity, thermostability, and storage stability of the immobilized SaLDH were significantly improved. In addition, the biotransformation of D-lactic acid to pyruvate catalyzed by SaLDH and the hybrid nanoflowers was investigated. The maximum conversion of D-... [more]

Curcumin is a hydrophobic bioactive compound, and its incorporation into lipid-based carriers can enhance its bioaccessibility and maintain its stability over time. Pickering emulsions are long-term stability systems, effective for encapsulation, protection, and delivery of bioactive compounds. This study aimed to produce Pickering oil-in-water (O/W) emulsions stabilized by cassava starch nanoparticles (native or modified by heat−moisture treatment (HMT)) with high kinetic stability to encapsulate curcumin. The effect of curcumin incorporation on emulsion features was also assessed, as well as curcumin stability over time. Native starch nanoparticles (NSNPs) were not effective stabilizers in the concentration range of 0.8 to 4 wt%. Otherwise, modified starch nanoparticles (HSNPs) at 4 wt% produced a long-term stability Pickering emulsion, which was used to encapsulate curcumin (0.07 wt%). Confocal laser scanning microscopy (CLSM) showed that HSNPs were located at the droplet’s interfac... [more]

Examining boiler failure causes is crucial for thermal power plant safety and profitability. However, traditional approaches are complex and expensive, lacking precise operational insights. Although data-driven approaches hold substantial potential in addressing these challenges, there is a gap in systematic approaches for investigating failure root causes with unlabeled data. Therefore, we proffered a novel framework rooted in data mining methodologies to probe the accountable operational variables for boiler failures. The primary objective was to furnish precise guidance for future operations to proactively prevent similar failures. The framework was centered on two data mining approaches, Principal Component Analysis (PCA) + K-means and Deep Embedded Clustering (DEC), with PCA + K-means serving as the baseline against which the performance of DEC was evaluated. To demonstrate the framework’s specifics, a case study was performed using datasets obtained from a waste-to-energy plant i... [more]

(1) Background: In this study, bioactive compounds (phenolics and betalains) extracted from beetroot were stabilized by encapsulation with maltodextrin and soy protein by the freeze drying method. Stability of bioactive compounds and bioactivities in a beetroot extract and encapsulates during 60 days of storage at 4 °C (without light) and at 25 °C (with and without light) were investigated. (2) Methods: Contents of bioactive compounds and bioactivity (antioxidant activity by DPPH, RP, and ABTS tests; anti-inflammatory and antihyperglycemic activity) were determined. Improvement in stability of bioactives’ content and bioactivity of prepared encapsulates in relation to the extract was observed after storage at room temperature under light conditions. (3) Results: Encapsulation with maltodextrin showed improvement in stability of all studied bioactive parameters, while an encapsulate with soy protein improved stability of bioactives and antioxidant activity compared to the extract. The e... [more]

The growing demand in industrial and biotechnological settings for more efficient enzymes with enhanced biochemical features, particularly thermostability and thermotolerance, necessitates a timely response. Renowned for their versatility, thermostable enzymes offer significant promise across a range of applications, including agricultural, medicinal, and biotechnological domains. This comprehensive review summarizes the structural attributes, catalytic mechanisms, and connection between structural configuration and functional activity of two major classes of thermostable enzymes: α-amylases and laccases. These enzymes serve as valuable models for understanding the structural foundation behind the thermostability of proteins. By highlighting the commercial importance of thermostable enzymes and the interest these generate among researchers in further optimization and innovation, this article can greatly contribute to ongoing research on thermostable enzymes and aiding industries in opt... [more]

Overlapping uranium and coal resources are widely distributed in the basins of China. The current uranium−coal coordinated mining model, mining interaction, and multi-phase and multi-field coupling mechanisms remain unclear, thereby substantially restricting the mining of overlapping uranium and coal resources. This article reviews the overlapping uranium−coal mining technology and conditions, summarizes the main problems faced by the coordinated mining of coexisting uranium−coal resources, proposes a dynamic coordinated mining technology system for the entire life cycle of coexisting uranium−coal resources, and describes the multiphase and multifield coordinated mining of co-associated uranium−coal resources. The multifield coupling mechanism clarifies the solid−liquid−gas three-phase spatiotemporal coupling effects of the stress, fracture, seepage, geochemical, pressure, and microbial fields, and explains the safe and efficient mining technology of uranium and coal resources, and the... [more]

The use of biobased substances derived from industrial and household waste as renewable raw materials for environmental applications is gaining prominence due to its sustainable and cost-effective approach to waste valorisation. Herein, we report the uptake of paraquat, a widely used pesticide, by magnetite nanoparticles coated with composted urban biowaste-derived substances (MNP-BBS). The magnetic nanoparticles were prepared using a modified co-precipitation method, and were characterized through various physicochemical techniques. They were tested as an adsorbent for paraquat removal under diverse experimental conditions, exploring the influence of pH (3−10), MNP-BBS dosages (200−1000 mg L−1), ionic strength (0−0.01 M), and presence of organic matter. The kinetic study revealed that the adsorption of paraquat onto MNP-BBS follows the pseudo-second-order model, reaching the adsorption equilibrium after 2 h of contact and 90% of paraquat removal in the best condition tested (1000 mg L... [more]

Gravels are widely distributed in the Baikouquan formation in the Mabei area of the Junggar Basin. However, conventional logging methods cannot quantitatively characterize gravel development, which limits the identification of lithology, structure, and sedimentary facies in this region. This study proposes a new method for automatically identifying gravels from electric imaging images and calculating gravel parameters utilizing the salient object detection (SOD) network. Firstly, a SOD network model (U2-Net) was constructed and trained using electric imaging data from the Baikouquan formation at the Mahu Sag. The blank strips in the images were filled using the U-Net convolutional neural network model. Sample sets were then prepared, and the gravel areas were labeled in the electric imaging images with the Labelme software in combination with image segmentation and human−machine interaction. These sample sets were used to train the network model, enabling the automatic recognition of g... [more]

The energy hub provides a comprehensive solution uniting energy producers, consumers, and storage systems, thereby optimizing energy utilization efficiency. The single integrated energy system’s limitations restrict renewable absorption and resource allocation, while uncoordinated demand responses create load peaks, and global warming challenges sustainable multi-energy system operations. Therefore, our work aims to enhance multi-energy flexibility by coordinating various energy hubs within a hydrogen-based integrated system. This study focuses on a cost-effective, ecologically sound, and flexible tertiary hub (producer, prosumer, and consumer) with integrated demand response programs, demonstrating a 17.30% reduction in operation costs and a 13.14% decrease in emissions. Power-to-gas technology enhances coupling efficiency among gas turbines, boilers, heat pumps, and chillers. A mixed-integer nonlinear programming model using a GAMS BARON solver will achieve the optimal results of thi... [more]

The diffusion behavior of polyurethane slurry in vertical cracks, especially rough cracks, is not clear and needs to be studied to provide an effective reference for grouting design. In this study, the diffusion morphology and characteristics of modified polyurethane slurry in vertical cracks were investigated through modeling tests using the line source grouting method. Based on the viscous time-varying characteristics of the slurry, a numerical model of slurry diffusion was established using the joint FVM-VOF method. The numerical model was found to be accurate and reliable compared to the test results. Finally, building upon the basic theory of three-dimensional structure, a rough surface model with Gaussian distribution, more consistent with reality, was established. A numerical simulation system was then employed to study the diffusion morphology and characteristics of slurry in different rough cracks. The results indicate that the diffusion of modified polyurethane slurry within... [more]

The global increase in antibiotics consumption has caused hazardous concentrations of these antimicrobials to be present in soils, mainly due to the spreading of sewage sludge (or manure or slurry) and wastewater, and they could enter the food chain, posing serious risks to the environment and human health. One of these substances of concern is cefuroxime (CFX). To face antibiotics-related environmental pollution, adsorption is one of the most widely used techniques, with cost-effective and environmentally friendly byproducts being of clear interest to retain pollutants and increase the adsorption capacity of soils. In light of this, in this work, three low-cost bioadsorbents (pine bark, oak ash, and mussel shell) were added to different soil samples (at doses of 12 and 48 t/ha) to study their effects on the adsorption of CFX. Specifically, batch experiments were carried out for mixtures of soils and bioadsorbents, adding a range of different antibiotic concentrations at a fixed ionic... [more]

In recent years, applications of inverse model-based control techniques have experienced significant growth in popularity and have been widely used in engineering applications, mainly in nonlinear control system design problems. In this study, a novel fuzzy internal model control (IMC) structure is presented for single-input-single-output (SISO) nonlinear systems. The proposed structure uses the forward and inverse dynamic Takagi−Sugeno (D-TS) fuzzy models of the nonlinear system within the IMC framework for the first time in literature. The proposed fuzzy IMC is obtained in a two-step procedure. A SISO nonlinear system is first approximated using a D-TS fuzzy system, of which the rule consequents are linearized subsystems derived from the nonlinear system. A novel approach is used to achieve the exact inversion of the SISO D-TS fuzzy model, which is then utilized as a control element within the IMC framework. In this way, the control design problem is simplified to the inversion probl... [more]

The drying process employed for camellia seeds has a significant impact on the quality of camellia seed oil (CO), but research on its influence on the flavor of CO is limited. This study investigated the effects of two typical drying processes, sun-drying and hot-air-drying, on the volatile composition of CO using Gas Chromatography-Ion Mobility Spectrometry (GC-IMS) technology. The results revealed that the CO obtained from hot-air-drying seeds exhibited a higher content of saturated fatty acids, while the levels of unsaturated fatty acids decreased. Additionally, the acid value and peroxide value of the CO obtained from hot-air-drying seeds were also elevated. GC-IMS analysis detected a total of 53 volatile compounds (including monomers and dimers) in the CO. Notably, aldehyde compounds exhibited the highest relative content (38.56−40.75%), followed by alcohols (32.14−38.01%), acids (4.86−14.58%), and esters (3.61−17.73%), while ketones exhibited relatively lower content (2.33−3.75%)... [more]

In this research, the effect of ultrasonic waves (UWs) on the heat transfer rate of a water-to-water double-pipe heat exchanger (DPHX) was investigated. To conduct the experiments, four ultrasonic transducers with similar sound frequencies of 40 kHz and a maximum power of 60 W were utilized. All the transducers were placed on the outer shell of the DPHX. The effects of the hot water flow rate and the temperature level of the hot water inlet, ranging from 40 to 60 °C in the central pipe, both in the absence and presence of UWs, were measured under UWs at different powers from 0 to 240 W. The performed experiments show that UWs increase the heat transfer rate, while the highest heat transfer rate improvement of 104% occurs at an inlet temperature of 60 °C and ultrasonic power level of 240 W. Given the scarcity of information regarding heat transfer behavior in ultrasonic-assisted DPHXs, these findings could illuminate the path for designing such heat exchangers.

Catalytic studies hydrogen production via steam reforming of ethanol (SRE) are essential for process optimization. Likewise, selecting the ideal support for the active phase can be critical to achieve high conversion rates during the catalytic steam reforming process. In this work, copper-based catalysts were synthesized using two different supports, NaY zeolite and Nb2O5/Al2O3 mixed oxides. The materials were prepared using wet impregnation and characterized for their physicochemical properties using different analytical techniques. Differences in the catalyst morphologies were readily attributed to the characteristics of the support. The Cu/NaY catalyst exhibited a higher specific surface area (210.40 m2 g−1) compared to the Cu/Nb2O5/Al2O3 catalyst (26.00 m2 g−1), resulting in a homogeneous metal dispersion over the support surface. The obtained results showed that, at 300 °C, both the Cu/Nb2O5/Al2O3 and Cu/NaY catalysts produced approximately 50% hydrogen and 40% acetaldehyde, but w... [more]

The aim of this research is to evaluate the impact of tomato pomace (TP) on the technological and sensory properties of ćevapi. Four treatments were prepared as follows: control (CON) and samples with the addition of TP in amounts of TP5 (0.5%—5 g/kg), TP10 (1%—10 g/kg), and TP20 (2%—20 g/kg). Technological properties (pH values, water activity (aw) cooking loss, length reduction), instrumental colour and texture, and sensory properties were examined. The addition of TP powder did not result in significant differences in pH and aw values between CON and modified treatments (in both raw and grilled). The addition of TP in the amounts higher than 10 g/kg significantly reduced cooking loss, while length reduction was observed when 20 g/kg was added. Also, significantly higher values of yellowness were observed in both the raw and grilled ćevapi, when 10 g/kg and more of TP was added. Significantly higher hardness and chewiness were observed in all experimental treatments. However, differe... [more]

Flow meters are extensively utilized in fields such as chemical engineering, petroleum, and aerospace, and are an indispensable component of modern industry. This paper examines the metrological properties of a dual-rotor turbine flow meter within its measurable flow range through experimental approaches and investigates the cavitation flow dynamics within the flow meter using numerical methods. First, the flow characteristics curve of the dual-rotor turbine flow meter was established experimentally, and the accuracy of numerical simulation results was validated. Secondly, the transient characteristics of the cavitation cavity were revealed using the Z-G-B cavitation model and dynamic mesh technology. Finally, entropy production theory was applied to investigate the energy losses caused by cavitation, analyzing the contributions of different types of energy losses during the cavitation process. Flow calibration experiments and numerical simulations reveal an increase in the meter coeff... [more]

Edge computing technology can effectively solve huge challenges posed by the large number of terminal devices accessing and massive data processing in digital distribution networks. Burst tasks, such as faults and data requests from the cloud, can occur at any time for edge computing devices in distribution networks. These tasks are unpredictable and usually hold the highest priority and must be completed as soon as possible. Although resources can be reserved partially at each period in the pre-scheduled operation plan, they may still be insufficient to handle burst tasks adequately. A real-time resource dispatch approach for burst tasks is developed in this study to address the above problems. The concept of flexibility for edge computing devices is presented, determining the real-time dispatch duration. Real-time resource dispatch and task handling processing are analyzed in detail, considered as task real-time dispatch models, computation process real-time dispatch constraints, and... [more]

Microwave applications, such as microwave ovens and mobile phones, are ubiquitous and indispensable in modern society. As the utilization of microwave technology is becoming more widespread, the effects of microwaves on living organisms and physiological processes have received increased attention. This study aimed to investigate the effects of microwaves on calcium carbonate biomineralization as a model biochemical process. A magnetron oscillator was used to generate 2450 MHz microwaves because magnetrons are relatively inexpensive and widespread. We conducted transmission electron microscopy (TEM), atomic force microscopy (AFM), TEM-electron energy-loss spectroscopy (EELS), dynamic light scattering (DLS), and high-performance liquid chromatography (HPLC) measurements to analyze the calcium carbonate precipitates. Our findings showed the formation of string-like precipitates of calcium carbonate upon microwave irradiation from one direction, similar to those obtained using a semicondu... [more]

Waste management in large urban centers is one of the main challenges for public administration. Two of the most abundant wastes in cities are waste solid and municipal wastewater (MWW). Their management can be optimized if they are treated together. This work analyzed an anaerobic−aerobic system for the treatment of fruit and vegetable wastes (FVWs) and MWW. Firstly, FVWs were collected and characterized; once in the laboratory, they were placed in a tank with the MWW, aiming at transferring to the water those solids with a particle size below 105 µm; then, they were separated by sieving. The mixture of MWW and FVWs with a particle size below 105 µm was fed into an up-flow anaerobic sludge reactor (UASB); in the latter, dissolved and suspended organic matter was transformed into methane and carbon dioxide. The water that left the UASB was sent to be post-treated in an activated sludge reactor (ASR). The chemical oxygen demand (COD) was used as an evaluation parameter of the anaerobic−... [more]

For the safe and efficient utilization of hydrogen-enriched natural gas combustion in industrial gas-fired boilers, the present study adopted a combination of numerical simulation and field tests to investigate its adaptability. Firstly, the combustion characteristics of hydrogen-enriched natural gas with different hydrogen blending ratios and equivalence ratios were evaluated by using the Chemkin Pro platform. Secondly, a field experimental study was carried out based on the WNS2-1.25-Q gas-fired boiler to investigate the boiler’s thermal efficiency, heat loss, and pollutant emissions after hydrogen addition. The results show that at the same equivalence ratio, with the hydrogen blending ratio increasing from 0% to 25%, the laminar flame propagation speed of the fuel increases, the extinction strain rate rises, and the combustion limit expands. The laminar flame propagation speed of premixed methane/air gas reaches the maximum value when the equivalence ratio is 1.0, and the combustio... [more]

The power sector is the single industry with the largest carbon emission in China, the carbon emission of which accounts for more than 40% of China’s total carbon emissions. In relevant research on the simulation of power system operation, current studies focus more on energy conservation and economical operation, while few consider the low-carbon optimization of the power system from the perspective of carbon emissions. In addition, in relevant research on carbon reduction in the power system, current studies focus more on controlling the direct carbon emission of the source side and less on the indirect carbon emissions of the load side, which focus on the reverse effect of a user’s electricity consumption behavior on the carbon reduction goals of the power system. This article delved into a deterministic simulation model of power system operation based on time series load curves and proposed a carbon reduction mechanism called the low-carbon demand response mechanism, which guides u... [more]

The problem of soil and Chuanxiong tuber congestion on vibrating screens usually exists during the Chuanxiong mechanized harvesting process. To address this problem, the conveyance performance of a crankshaft rocker vibrating screen was studied. By establishing and solving the dynamics and kinematics equations for the crankshaft rocker vibrating mechanism and Chuanxiong soil residue, the acceleration of the vibrating screen and Chuanxiong-soil residue was studied. The sliding speed, motion process, and conveying distance of the Chuanxiong soil residue were also analyzed. The theoretical analysis results indicated that the acceleration of the vibrating screen depends on the rod lengths of the vibrating mechanism and the crank rotational speed and position. The displacement of the Chuanxiong-soil residue along the positive sliding direction in a cycle was more significant than that of the negative sliding direction. The appropriate advancement speed of the harvester was also obtained. Th... [more]

At low temperatures, PMMA surfaces are prone to ice and frost formation, which presents a significant challenge for PMMA’s efficient application in cold environments due to the difficulty in physically removing the accumulated ice. Superhydrophobic surfaces exhibit promising potential in passive anti-icing strategies. To exploit this advantage, we employed femtosecond laser technology to create six distinct microstructured PMMA surfaces, followed by surface modification using 1H,1H,2H,2H-perfluorodecyltriethoxysilane, resulting in enhanced hydrophobic and anti-icing properties. Among the tested structures, a secondary circular dot pattern achieved a remarkable contact angle of 153.7°, prolonging the freezing duration by approximately 40% at −10 °C, and reducing frost accumulation by over 50%. The ice adhesion strength was significantly reduced to 34 kPa. These findings contribute to broadening the applicability of PMMA and advancing the use of superhydrophobic surfaces in anti-icing ap... [more]

Hyperparameter tuning is crucial in the development of machine learning models. This study introduces the nonlinear shrinking factor and the Cauchy mutation mechanism to improve the Dujiangyan Irrigation System Optimization (DISO), proposing the improved Dujiangyan Irrigation System Optimization algorithm (IDISO) for hyperparameter tuning in machine learning. The optimization capabilities and convergence performance of IDISO were validated on 87 CEC2017 benchmark functions of varying dimensions and nine real-world engineering problems, demonstrating that it significantly outperforms DISO in terms of convergence speed and accuracy, and ranks first in overall performance among the seventeen advanced metaheuristic algorithms being compared. To construct a robust and generalizable prediction model for hydrochar element characteristics, this study utilized IDISO and DISO algorithms to fine-tune the parameters of the XGBoost model. The experimental results show that the IDISO-XGBoost model a... [more]