Osmotic dehydration is a pre-treatment given prior to finish drying or freezing preservation to improve quality and/or minimize the damaging effects on quality parameters, by partially reducing the moisture content of the sample. Pineapple titbits were partially dried using microwave assisted osmotic dehydration under continuous flow medium spray condition (MWODS) and then frozen with or without a sodium alginate−calcium chloride-based edible coating. The effects of MWODS pre-treatment and edible coating on the quality parameters of pineapple titbits frozen and stored at −20 °C for 10 and 50 days were evaluated after thawing. Both treatments (MWODS and alginate) resulted in superior quality products as compared to the control sample. MWODS, with its advantages over the conventional osmotic dehydration (COD) of rapid and higher moisture removal (16% in 10 min vs. 4 h in COD), while limiting solids gain (2.5% MWODS vs. 4.5% in COD), resulted in improved quality over the control during th... [more]

To investigate the brittleness of shale and its influencing factors, triaxial rock mechanics experiments, combined with X-ray diffraction, total organic carbon (TOC) measurement, rock pyrolysis, and scanning electron microscopy, were conducted on shales from the Jurassic Lianggaoshan Formation in the Sichuan Basin. BI1, based on the elastic modulus and hardness, BI2, based on mineral composition, BI3, based on strength parameters, and BI4, based on the post-peak energy of shale, were calculated. Additionally, the effects of mineral composition, density, hardness, and organic matter on the brittleness of shales were analyzed. The results show that the shale mineral compositions were dominated by quartz (mean of 45.21%) and clay minerals (mean of 45.04%), with low carbonate mineral contents and high TOC contents. The stress−strain curve showed strong brittleness characteristics. When comparing different evaluation methods, the brittleness evaluation method based on the stress−strain curv... [more]

We demonstrated soldering of an electrical component (the metal-oxide semiconductor field effect transistor (MOSFET)) on a printed circuit bord (PCB) via solder paste heated by microwave irradiation. The behavior of the object soldered with solder heated in a microwave magnetic field and electric field were evaluated by using various microwave resonators. In the magnetic field, the solder paste was selectively heated by microwave irradiation. We confirmed that the MOSFET was connected onto the PCB without any damage and that the MOSFET operated normally. However, in an electric field, the solder paste cannot be heated by microwave irradiation because the edges of the PCB were selectively heated. Consequently, the MOSFET could not be connected onto the PCB. The strengths of the electromagnetic fields produced by different microwave resonators were numerically simulated to determine the optimal positions for microwave soldering. Based on the simulation results, microwave heating with sep... [more]

The main purpose of this paper was to study the vertical settlement of offshore wind turbine (OWT) monopile support structures, where 5, 10, 15, and 20 MW OWT support structures were analyzed under power production, seismic, and tropical cyclone loads. Moreover, a t-z spring with shear and torsional degrees of freedom was developed to simulate the shear stress along the pile and soil surface under the combined effect of vertical loads and z-direction torsions. This t-z spring does not require excessive changes to the finite element program, where only a known factor is used to modify the traditional stiffness of the t-z spring. This paper, analyzing several kinds of OWT monopile foundations, indicates that the soil shear resistance may be less than the shear stress generated by the combination of vertical loads and torsions, which causes large vertical and rotational displacements resulting in the failure of monopile structures. This situation will be worse when the natural frequency o... [more]

Cellulose acetate (CA) is a semisynthetic, biodegradable polymer. Due to its characteristics, CA has several applications, including water membranes, filament-forming matrices, biomedical nanocomposites, household tools, and photographic films. This review deals with topics related to the CA membranes, which are prepared using different techniques, such as the phase inversion technique. CA membranes are considered very important since they can be used as microfiltration membranes (MF), ultrafiltration membranes (UF), nanofiltration membranes (NF), reverse osmosis (RO) membranes, and forward osmosis (FO) membranes. Membrane fouling results from the accumulation of materials that the membrane rejects on the surface or in the membrane’s pores, lowering the membrane’s flux and rejection rates. There are various forms of CA membrane fouling, for instance, organic, inorganic, particulate fouling, and biofouling. In this review, strategies used for CA membrane antifouling are discussed and su... [more]

At present, the formation mechanism of gas hydrate (hereinafter referred to as hydrate) plugging in the wellbore during deepwater drilling is not clear, so there are problems such as the overuse of hydrate inhibitors and the low utilization efficiency of inhibitors. Therefore, in view of the risk of hydrate formation and plugging under different working conditions during deepwater drilling, research was carried out on the wellbore hydrate formation area and wellbore hydrate deposition and plugging. Taking an atmospheric well in the South China Sea as an example, the wellbore annulus temperature field under different working conditions was combined with the hydrate formation phase curve to analyze the hydrate formation plugging risk under different working conditions during deepwater drilling, and the hydrate formation risk region of the wellbore under different working conditions was obtained. The effects of the drilling fluid circulation rate, injection temperature and drilling fluid... [more]

As an important production factor of grain production, agricultural machinery can effectively provide a theoretical basis for agricultural modernization development strategies by exploring its impact on grain production capacity and efficiency. This research starts from the two aspects of grain production capacity and grain production efficiency, takes rice, wheat, and corn as the research objects, and uses the C−D production function and Tobit model as the basis, respectively, to establish two impact models of production capacity and production efficiency. At the same time, according to the different emphases of the two models, this research designs different variable systems and finally uses the data from 2017 to 2021 for empirical analysis. The research results show that the influence coefficients of machinery service income and machinery power resource input on the total grain production capacity are 0.0976 and 0.0437, respectively, with a significant positive impact. At the same t... [more]

The classification of GM and non-GM maize kernels is fundamental for further analysis of the gene action in maize. Therefore, a complete and novel detection scheme based on near-infrared spectra was designed to distinguish GM and non-GM maize kernels. Hyperspectral images (935−1720 nm) of 777 maize kernels from 3 kinds were captured, and the average spectra of the maize kernels were extracted for modeling analysis. The classical modeling methods based on feature engineering were first studied, and the backpropagation neural network−genetic algorithm model showed the best performance with a prediction accuracy of 0.861. Then, novel modeling methods based on deep learning were developed. To dig out the interactive information between different bands and match the application scenarios, the original spectra were transformed into two-dimensional matrices before establishing the deep learning models. A modified convolution neural network (i.e., VGG net) with dilated convolution was finally... [more]

The vehicle model was built based on MATLAB/Simulink and Carsim, and the multi-objective active collision avoidance control algorithm considering safety and comfort was established based on a model predictive control (MPC) algorithm. The vehicle active collision avoidance control system for comfort and safety was studied by simulation and experimentation. The results show that the active collision avoidance control system based on an MPC algorithm can follow the vehicle under different working conditions and ensure the safety and comfort in the process of following the vehicle while meeting the requirements of the active collision avoidance control system.

In this study, a three-dimensional CFD transient model is established for predicting species concentration distribution in the biodegradation of phenol in an airlift reactor (ALR). The gas−liquid flow in the ALR is determined by the Euler−Euler method coupled with the standard k-ε model, and the bubble size is predicted by the population balance model (PBM). A turbulent mass diffusivity model is developed to simulate the turbulent mass transfer process and to predict the species concentration distribution. No empirical methods are needed as the turbulent mass diffusivity can be expressed by the concentration variance c2¯ and its dissipation rate εc. A good agreement is found between simulated and experimental results in the literature. It is not reasonable to assume a constant turbulent Schmidt number because the calculated distribution of turbulent mass diffusivity is not identical to that of turbulent viscosity. Finally, the hydrodynamic characteristics and biodegradation performance... [more]

This article’s goal was to explain how chemical reaction and viscous dissipation affect a non-Newtonian Cross-fluid in a boundary layer flow due to a stretching sheet with variable fluid properties. The results were obtained after assuming laminar, steady, and viscous flow characteristics. In this study, the analysis took into account the characteristics of the fluid variable diffusivity and slip velocity. It was considered that fluid viscosity and thermal conductivity are temperaturedependent variables. Because of their mobility, non-Newtonian fluid particles are thought to interact chemically. The physical problem is governed by a set of partial differential equations that are not linear. Anumerical solution was reached usingNewton’s shooting methodology and the Runge−Kutta integration technique. A set of figures displays the distributions of the temperature, concentration, and velocity at various physical parameter values. The influence of all physical parameters is shown in tabular... [more]

Madeira wine is produced via spontaneous alcoholic fermentation arrested by ethanol addition. The increasing demand of the wine market has led to the need to standardize the winemaking process. This study focuses on identifying the microbiota of indigenous yeasts present during Madeira wine fermentation and then evaluates the impact of selected indigenous non-Saccharomyces as pure starter culture (Hanseniaspora uvarum, Starmerella bacillaris, Pichia terricola, Pichia fermentans, and Pichia kluyveri) in the chemical and phenolic characterization of Madeira wine production. Results showed that the polyphenol content of the wines was influenced by yeast species, with higher levels found in wines produced by Pichia spp. (ranging from 356.85 to 367.68 mg GAE/L in total polyphenols and 50.52 to 51.50 mg/L in total individual polyphenols through HPLC methods). Antioxidant potential was higher in wines produced with Hanseniaspora uvarum (133.60 mg Trolox/L) and Starmerella bacillaris (137.61 m... [more]

Flood disasters are a natural occurrence around the world, resulting in numerous casualties. It is vital to develop an accurate flood forecasting and prediction model in order to curb damages and limit the number of victims. Water resource allocation, management, planning, flood warning and forecasting, and flood damage mitigation all benefit from rain forecasting. Prior to recent decades’ worth of research, this domain demonstrated to be promising prospects in time series prediction tasks. Therefore, the main aim of this study is to build a forecasting model based on the exponential smoothing-long-short term memory (ES-LSTM) structure and recurrent neural networks (RNNs) for predicting hourly precipitation seasons; and classify the precipitation using an artificial neural network (ANN) model and decision tree (DT) algorithm. We employ the dataset from the Australian commonwealth office of meteorology named Historical Daily Weather dataset to test the effectiveness of the proposed mode... [more]

At present, great progress has been made in the prediction of undercompaction and fluid expansion overpressure. However, in recent years, the field has frequently encountered pressure relief-type overpressure. Different from primary overpressure, such as undercompaction and fluid expansion, this type of overpressure belongs to secondary overpressure, which has a certain concealment in response to seismic velocity and logging data. Based on this, a geological analysis model of pressure relief-type overpressure was established according to the seepage and stress coupling theory. The model can realize the prediction of pressure relief range and pressure distribution, which provides a new way to predict this kind of overpressure. The influence of the laws of porosity, permeability, and geological movement on pressure relief were analyzed. The research results provide a new method for the prediction of pressure relief-type overpressure and improving the basic guarantee of safe and efficient... [more]

Recent research papers have confirmed the prevalence of microorganisms resistant to numerous antimicrobial agents, leading to spreading infections, extended hospitalizations, and increased mortality rates. The amplifying factors stimulate the need to discover new molecules able to cut off the developing resistance of pathogens against medicines. The current study presents a molecular docking procedure applied on 15 new pyridine−thiourea derivatives in order to test their activities against S. aureus and E. coli. The protein crystal structures were obtained from the Protein Data Bank (PDB). Processes such as geometry optimization, molecular properties (log P, polarizability, E HOMO, E LUMO, area and volume of the molecules, and ovality), drug-likeness, pharmacokinetic and pharmacogenomic profiles, and molecular docking studies are discussed in the present research. The approach involved the determination of the molecular properties for each chemical structure by using the Spartan 14 sof... [more]

Wastewater treatment and reuse are being regarded as the most effective strategy for combating water scarcity threats. This study examined and reported the applications of the Internet of Things (IoT) and artificial intelligence in the phytoremediation of wastewater using Salvinia molesta plants. Water quality (WQ) indicators (total dissolved solids (TDS), temperature, oxidation-reduction potential (ORP), and turbidity) of the S. molesta treatment system at a retention time of 24 h were measured using an Arduino IoT device. Finally, four machine learning tools (ML) were employed in modeling and evaluating the predicted concentration of the total dissolved solids after treatment (TDSt) of the water samples. Additionally, three nonlinear error ensemble methods were used to enhance the prediction accuracy of the TDSt models. The outcome obtained from the modeling and prediction of the TDSt depicted that the best results were observed at SVM-M1 with 0.9999, 0.0139, 1.0000, and 0.1177 for R... [more]

As an important component of hydrogen fuel cell vehicles, the air compressor with an air foil bearing rotates at tens of thousands of revolutions per minute. The heat generation concentration problem caused by the high-speed motor loss seriously affects the safe and normal operation of the motor, so it is very important to clarify the loss distribution of the high-speed motor and adopt a targeted loss reduction design for air compressor heat dissipation. In this paper, for an air compressor with a foil bearing with a rated speed of 80,000 rpm, an empirical formula and a three-dimensional transient magnetic field finite element model are used to model and calculate the air friction loss, stator core loss, winding loss and permanent magnet eddy current loss. The accuracy of the analytical calculation method is verified by torque test experiments under different revolutions, and the average simulation accuracy can reach 91.1%. Then, the distribution of the air friction loss, stator core l... [more]

The paver needs superior constant speed performance when paving the pavement. In order to effectively reduce the paver speed fluctuation of the paver, and the wandering deviation from the predetermined track during the paving operation, a control scheme of paver travelling system based on GNSS, Global Navigation Satellite System, is proposed; the scheme can realize open-loop control, closed-loop control, and deviation correction control according to the driver’s choice. During closed-loop control, the setting value and the PID controller output of the left wheel are combined to control the speed of the left wheel, as is the closed-loop control of the right wheel. During the deviation correction control, the coordinate provided by the RTK GNSS receiver and the predetermined trajectory line are used to calculate the lateral deviation of the paver. The lateral deviation is input to the right wheel navigation correction PID algorithm. After the calculation, the correction value of the righ... [more]

As a fuel for power generation, high-pressure hydrogen gas is widely used for transportation, and its efficient storage promotes the development of fuel cell vehicles (FCVs). However, as the filling process takes such a short time, the maximum temperature in the storage tank usually undergoes a rapid increase, which has become a thorny problem and poses great technical challenges to the steady operation of hydrogen FCVs. For security reasons, SAE J2601/ISO 15869 regulates a maximum temperature limit of 85 °C in the specifications for refillable hydrogen tanks. In this paper, a two-dimensional axisymmetric and a three-dimensional numerical model for fast charging of Type III, 35 MPa, and 70 MPa hydrogen vehicle cylinders are proposed in order to effectively evaluate the temperature rise within vehicle tanks. A modified standard k-ε turbulence model is utilized to simulate hydrogen gas charging. The equation of state for hydrogen gas is adopted with the thermodynamic properties taken fro... [more]

A transformer is an important part of the power system. Existing transformer fault diagnosis methods are still limited by the accuracy and efficiency of the solution and excessively rely on manpower. In this paper, a novel neural network is designed to overcome this issue. Based on the traditional method of judging the ratio of dissolved gas in transformer internal insulation oil, a fast fault diagnosis model of a transformer was built with an improved probabilistic neural network (PNN). The particle swarm optimization (PSO) algorithm was used to find the global optimal smoothing factor and improve the fault diagnosis accuracy of PNN. The transformer fault diagnosis model based on improved PNN not only eliminates the influence of human subjective factors but also significantly improves the diagnosis speed and accuracy, meeting the requirements for real-time application in practical projects. The feasibility and effectiveness of the method proposed in this paper are illustrated by a cas... [more]

Particle formation in fluidized beds is widely applied in an industrial context for the solidification of liquids and size enlargement of granular materials. The two main size-enlargement mechanisms are layering growth and agglomeration. For continuous process configurations with sieve-mill-recycle and layering growth only, the occurrence of undesired self-sustained oscillations in the particle size distribution under certain process conditions is well-known. This contribution investigates the stability of the practically relevant process with additional particle agglomeration by means of a model-based numerical bifurcation analysis. It is shown that the occurrence of stable limit cycles is inhibited by an increased rate of particle agglomeration for a variety of different process conditions and different agglomeration kinetics. These results enhance the understanding of the agglomeration and layering growth dynamics and are relevant for the process design and operation.

Despite the globally increasing use of platinum-based cytostatic drugs in the treatment of several types of cancer, only limited attention has been paid to developing a treatment for contaminated liquid samples originating from hospitals, laboratories and manufacturing facilities before and after their administration. In this work, we assess the efficiency of a low-cost adsorbent material, a dithiocarbamate-functionalized silica, in removing cisplatin from a solution containing it in the 0.5−150 mg L−1 concentration range. The advantage of having a surface-functionalized silica is that adsorption can occur by either non-covalent interaction or surface complexation. In the latter case platinum(II) is de-complexed and the original drug is no longer present. Adsorption occurs through a first rapid step, followed by a second slower process. This is likely due to the fact that in our operating conditions (0.9% w/v NaCl), only the original compound is present, for which ligand substitution i... [more]

This paper aims to quantitatively analyze the influence of natural groundwater flowing into the flow field of in situ leaching mining. The computational method was built to evaluate the effect of natural groundwater on the production efficiency of pumping wells for the in situ leaching of uranium, and the “flow ratio of groundwater” and related formulas were defined. C1 and C2 mining areas of an in situ leaching uranium mine in Inner Mongolia were taken as an example, and the effect on the “flow ratio of groundwater” when changing the flow quantity of injection wells and the position and length of the filter in the pumping and injection wells were compared. The results show that the variation in the “flow ratio of groundwater” of a whole mining area or a single pumping well in different production stages can be obtained by the neutral solution concentration value from the mining area’s numerical simulation. Regulating the position, length of the filter, and mode of fluid injection in a... [more]

Innovations in food drying processes are usually aimed at reducing drying time and improving the overall properties of dried products. These are important issues from an economic and environmental point of view and can contribute to the sustainability of the whole process. In this study, the effects of ultrasonic treatment on the drying kinetics of pumpkin pulp are investigated, and mathematical models to predict the drying kinetics are analyzed and optimized. The results show that ultrasonic pretreatment significantly reduces drying time from 451 to 268 min, with optimal processing parameters at 90% of the maximum ultrasonic power and a processing time of 45 min. The total color change of the samples was the lowest at the obtained optimal processing parameters. Based on the values (RMSE and R2) of the investigated mathematical drying models, it was found that the Weibull model is the best fit for the experimental data and is considered suitable for the drying kinetics of ultrasonicall... [more]

This review presents the nucleate/convective boiling performance for a variety of important low global warming potential (LGWP) alternatives to commonly used high-global warming potential (GWP) refrigerants (such as R-134a, R404A, and R-410A, etc.). Efforts are stressed on the assessment of their evaporation pressure drop and heat transfer coefficient (HTC) characteristics. These alternatives include R-1234ze(Z), R-1234ze(E), R-1233zd (E), R-1234ze(E), R-410A, R-1234yf, and R-513A. The authors investigated the thermo-fluid properties within and outside a tube, mini-channel, micro-fin tube, and plate heat exchanger. The investigation of the numerical, experimental, and simulated results revealed that the evaporation pressure drop and HTC characteristics were dependent on a variety of variables. These factors include the working fluid’s thermodynamics and transport properties, the refrigerant’s mass flux, heat flux, saturation temperature, the vapor quality, the conditions and flow patte... [more]