As a new highly damage-tolerant structural material, the TC21 titanium alloy has been widely used in aerospace applications. Inertial friction welding (IFW) is a form of pressure welding technology with less welding parameters and high welding joint performance, which is especially suitable for the connection of rotors of aero-compressors and engines. In this paper, inertia friction welding of TC21 titanium alloys was successfully carried out, and the microhardness, tensile properties and low cycle fatigue (LCF) behaviors of IFW joints were studied. Based on the mechanical parametric results of the tensile test, the true stress−strain curves of the IFW joint of TC21 titanium alloys are obtained by further calculation. Based on the LCF test results under different strain amplitudes, life prediction of IFW joints was investigated. The results of the LCF test show that there is no obvious cyclic hardening and cyclic softening of the IFW joints. Moreover, the fracture morphology of LCF sam... [more]

Under the guidance of China’s goal of achieving carbon neutrality by 2060, the petrochemical industry is increasingly adopting energy-saving and emission-reduction technologies. To realize the low carbon operation of the LNG (liquefied natural gas) receiving terminal, an innovative SCV (submerged combustion vaporizer) flue gas carbon capture system using LNG cold energy was established, and the system also combined with an ORC (organic Rankine cycle). HYSYS software was used to simulate the process of the SCV flue gas carbon capture system and the LNG regasification system. The simulation results showed that the proposed system has low carbon emission and low energy consumption performance. Moreover, the sensitivity analysis of the evaporation pressure of working fluids, CO2 capture pressure, and CO2 capture temperature was carried out. The key parameters were optimized by HYSYS software to achieve the optimal operation cost of the system. When the evaporation pressure of working fluid... [more]

For locating the source of leaking gas in various engineering fields, several issues remain in the immediate estimation of the location of diffusion sources from limited observation data, because of the nonlinearity of turbulence. This study investigated the practical applicability of diffusion source-location prediction using a convolutional neural network (CNN) from leaking gas instantaneous distribution images captured by infrared cameras. We performed direct numerical simulation of a turbulent flow past a cylinder to provide training and test images, which are scalar concentration distribution fields integrated along the view direction, mimicking actual camera images. We discussed the effects of the direction in which the leaking gas flows into the camera’s view and the distance between the camera and the leaking gas on the accuracy of inference. A single learner created by all images provided an inference accuracy exceeding 85%, regardless of the inflow direction or the distance b... [more]

In the Supercritical Antisolvent process (SAS), the thermodynamic behavior of complex multicomponent systems can influence the particles’ morphology. However, due to the limited thermodynamic data for multicomponent systems, the effect of solutes is often neglected, and the system is considered as pseudo-binary. It has been demonstrated that the presence of a solute can significantly influence the thermodynamic behavior of the system. In particular, when the SAS process is adopted for the production of drug/polymer coprecipitated microparticles, the effect of both the drug and the polymer in the solvent/CO2 mixture should be considered. In this work, the effect of polyvinylpyrrolidone (PVP), used as the carrier, and of the liposoluble vitamins menadione (MEN) and α-tocopherol (TOC), as model drugs, was investigated as a deviation from the fundamental thermodynamic behavior of the DMSO/CO2 binary system. Vapor−liquid equilibria (VLE) were evaluated at 313 K, with a PVP concentration in... [more]

This study simulated seabed high pressure and low temperature conditions to synthesize natural gas hydrates, multi-stage depressurization mode mining hydrates as the blank group, and then carried out experimental research on the decomposition and mining efficiency of hydrates by depressurization and injection of different alcohols, inorganic salts, and different chemical agent concentrations. According to the experimental results, the chemical agent with the best decomposition efficiency is preferred; the results show that: the depressurization and injection of a certain mass concentration of chemical agents to exploit natural gas hydrate is more effective than pure depressurization to increase the instantaneous gas production rate. This is because depressurization combined with chemical injection can destroy the hydrate phase balance while effectively reducing the energy required for hydrate decomposition, thereby greatly improving the hydrate decomposition efficiency. Among them, dep... [more]

The high chloride content of municipal solid waste incineration (MSWI) fly ash and hazardous waste incineration (HWI) fly ash has considerably affected their disposal. This study focused on investigating the three-stage counter-current (TSC) water-washing process to reduce the chlorine content efficiently under the premise of low water consumption. The liquid−solid ratio (LSR) and washing time were investigated, a chloride migration model was established, and the characteristics of the water-washing solution (WWS) and washed fly ash were investigated. The results showed that the dechlorination effect of TSC washing could reach more than 99% in a low liquid−solid ratio (LSR) of 2−4 kg/L. The most appropriate LSR and washing time were found to be around 3:1 L/kg and 15 min per stage, respectively. The concentration of Cl− in WWS reached over 90 g/L, which is very high among industrial saline wastewater. Some heavy metals were also contained in the WWS, and lead was the main heavy metal,... [more]

In practice, R&D in public organizations in developing countries is confronted with a variety of failures related to supporting management disciplines. The primary goal of this study is to address this issue through multiple-criteria decision making, which includes the DANP (DEMATEL-based ANP) approach. The DANP approach helps to resolve the classification issue that arises as a result of interdependence and feedback characteristics among the capabilities related to supporting management disciplines, allowing weak capabilities to be prioritized based on their interdependence. In the case of criteria weighting, the empirical result in terms of the degree of the net causal relationship had a greater influence on other criteria; however, in terms of dimensions, the technology management process capability had a greater significance on other dimensions, while the innovation management process capability had the least significance on other dimensions. The studies were based on relevant capa... [more]

In this study, the effect of hydrothermal liquefaction (HTL) of waste PVC was investigated in the presence of acidic hydrochar. The hydrochar was prepared by hydrothermal carbonization of pineapple waste at 250 °C and at 1 h in the presence of citric acid. Hydrochar was acidic, stable, and porous and contained acidic functional groups. Hydrochar was co-fed with PVC during HTL to enhance HTL conversion and quality of the plastic crude oil. HTL experiments were performed at 300−350 °C, 0.25−4 h of reaction times, and 0−20 wt% hydrochar-to-PVC ratio. The plastic crude oil was separated from the solid residue to evaluate HTL conversion and to analyze elemental compositions, boiling point distribution, alteration of chemical bonds, and chemical compositions. The results showed that acidic hydrochar enhances HTL conversion with a maximum value of 28.75 at 5 wt% hydrochar content at 350 °C and 0.5 h. Furthermore, plastic crude oils contained no chloride but contained significantly high carbon... [more]

This paper presents a simulation of an insulated micro-grid system based on the three-level converters control for energy management. Different renewable power sources (wind turbine and Photovoltaic (PV) energy systems) are used to energize the micro-grid. However, a battery energy storage system (BESS) and a variable diesel generator are also used to improve the reliability of the system. The contribution of this research is focused on the power control method based on improving the quality of energy transfer, mastering dynamic interactions and maximum energy production from renewable energies to reduce the fuel consumption by the diesel. Firstly, the proposed control model for each renewable energy was carried out through simulation in the environments of Matlab and Simulink to test the robustness and performance. The second part of this research is dedicated to managing the sharing of power between load, generators, and storage systems by extracting the references of power. The thre... [more]

Alumina concentration is an important parameter in the production process of aluminum electrolysis. Due to the complex production environment in the industrial field and the complex physical and chemical reactions in the aluminum reduction cell, nowadays it is still unable to carry out online measurement and real-time monitoring. For solving this problem, a soft-sensing model of alumina concentration based on a deep belief network (DBN) is proposed. However, the soft-sensing model may have some limitations for different cells and different periodic working conditions such as local anode effect, pole changing, and bus lifting in the same cell. The empirical mode decomposition (EMD) and particle swarm optimization (PSO) with the DBN are combined, and an EMD−PSO−DBN method that can denoize and optimize the model structure is proposed. The simulation results show that the improved soft-sensing model improves the accuracy and universality of prediction.

Essential oils (EOs) from Abies sachalinensis (Sakhalin fir), a conifer species found in Sakhalin Island and Hokkaido in Japan, effectively remove nitrogen dioxide and possess antifungal activity. EOs also exert a relaxing effect and enhance air quality. Underwater shock waves generate instantaneous high pressure that ruptures cell walls, enhancing the performance of steam distillation and oil extraction. In this study, we aimed to increase the yield and quality of A. sachalinensis extracts using shockwaves. Leaves and branches were subjected to shockwave pretreatment or left untreated before EO extraction by steam distillation. EO yield of untreated dried leaves was 2.4 g/kg of dry leaf weight (DW). Upon application of a 3.0 kV, 3.6 kJ shockwave, the yield increased with the number of shockwave cycles. After ten cycles, yield increased 13.6-fold. Pretreatment with shockwaves for 10 cycles resulted in approximately 6- and 13-fold reductions in total energy consumption relative to fresh... [more]

The search for novel highly effective materials with target properties for different electrochemical purposes is active for now. Ceramic materials with high levels of ionic conductivity can be applied as electrolytic materials in solid oxide fuel cells and in electrolyzers. Layered perovskites are a novel class of ionic conductors demonstrating almost-pure proton transportation at mid-temperatures. Gadolinium-doped ceramic materials based on layered perovskite BaLa2In2O7 were obtained and investigated for the first time in this study. The effect of the dopant concentrations on the hydration processes and on ionic conductivity was revealed. It was shown that compositions 0 ≤ x ≤ 0.15 of BaLa2−xGdxIn2O7 exhibited proton conductivity when under wet air and at mid-temperatures (lower than ~450 °C). Gadolinium doping led to an increase in the conductivity values up to an order of magnitude of ~0.5. The protonic conductivity of the most conductive composition BaLa1.85Gd0.15In2O7 was 2.7∙10−6... [more]

The technology of radial-well-assisted hydraulic fracturing is applied in the stimulation of low-permeability hydrocarbon reservoirs where commercial production cannot be achieved by the conventional fracturing method. Here, a study on the reservoir stimulation effect and the fracture propagation pattern of radial-well-assisted deflagration fracturing was carried out. Based on smooth particle hydrodynamics (SPH), rock mechanics theory, and finite element theory, a numerical model of radial-well-assisted deflagration fracturing was established by integrating the JWL state equation. Research on the effects of the deflagration position, radial well azimuth and horizontal principal stress difference on the fracture propagation was carried out. The results show that the deflagration position, radial well azimuth and horizontal principal stress difference have significant effects on the fracture area in deflagration fracturing. The closer distance from the deflagration position is, the large... [more]

When drilling or exploiting fractured formations, gas fluid displacement and invasion often occur, and gas invasion is very subtle and difficult to find. The gas in the fracture enters the wellbore and arrives near the wellhead with the drilling fluid. Improper treatment may lead to serious accidents such as lost circulation and blowout. In this study, using computational fluid dynamics (CFD) simulation software for modeling and grid generation, based on the volume of fluid (VOF) method, the gas invasion behavior under different conditions was simulated to explore the flow process and characteristics of gas invasion, and the effects of different drilling fluid properties and fracture morphology on gas invasion were analyzed. The experimental results show that the drilling fluid enters the fracture to compress the gas, making the pressure in the fracture greater than that in the wellbore, thus leading to the occurrence of gas invasion. The viscosity and density of the drilling fluid hav... [more]

In this paper, a novel composite fault diagnosis method combining adaptive feature mode decomposition (FMD) and minimum noise amplitude deconvolution (MNAD) is proposed. Firstly, chaos mapping and leader mutation selection strategy were introduced to improve the Northern Goshawk algorithm (NGO), and a chaotic leadership Northern Goshawk optimization (CLNGO) algorithm was proposed. The advantages of the CLNGO algorithm in convergence accuracy and speed were verified by 12 benchmark functions. Then, a new index called sparse pulse and cyclicstationarity (SPC) is proposed to evaluate signal sparsity. Finally, SPC is used as the fitness function of CLNGO to optimize FMD and MNAD. The optimal decomposition mode n and filter length of FMD, and filter length L and noise ratio ρ of MNAD are selected. The CLNGO-FMD is used to decompose signal into different modes. The signal is reconstructed based on the kurtosis criterion and the CLNGO-MNAD method is used to reduce the noise of the reconstruct... [more]

Biotrickling filtration is a well-established technology for the treatment of air polluted with odorous and volatile organic compounds (VOCs). Besides dozens of successful industrial applications of this technology, there are still gaps in a full understanding and description of the mechanisms of biotrickling filtration. This review focuses on recent research results on biotrickling filtration of air polluted with single and multiple VOCs, as well as process modeling. The modeling offers optimization of a process design and performance, as well as allows deeper understanding of process mechanisms. An overview of the developments of models describing biotrickling filtration and conventional biofiltration, as primarily developed and in many aspects through similar processes, is presented in this paper.

The modeling and simulation of combustion processes is still a challenging field [...]

Temperature is one of the most important parameters in the combustion processes. Accurate surface temperature can help to gain insight into the combustion characteristics of various solid or liquid fuels, as well as to evaluate the operating status of combustion power facilities such as internal combustion engines and gas turbines. This paper mainly summarizes and compares the main surface thermometry techniques, from the aspects of their principles, current state of development, and specific applications. These techniques are divided into two categories: contact-based thermometry and non-intrusive thermometry. In contact-based thermometry, conventional thermocouples as well as thin-film thermocouples are introduced. These methods have been developed for a long time and are simple and economical. However, such methods have disadvantages such as interference to flow and temperature field and poor dynamic performance. Furthermore, this paper reviews the latest non-intrusive thermometry m... [more]

In manufacturing processes using computerized numerical control (CNC) machines, machine tools are operated repeatedly for a long period for machining hard and difficult-to-machine materials, such as stainless steel. These operating conditions frequently result in tool breakage. The failure of machine tools significantly degrades the product quality and efficiency of the target process. To solve these problems, various studies have been conducted for detecting faults in machine tools. However, the most related studies used only the univariate signal obtained from CNC machines. The fault-detection methods using univariate signals have a limitation in that multivariate models cannot be applied. This can restrict in performance improvement of the fault detection. To address this problem, we employed empirical mode decomposition to construct a multivariate dataset from the univariate signal. Subsequently, auto-associative kernel regression was used to detect faults in the machine tool. To v... [more]

This study aimed to isolate, purify, and identify some bacteria from different sources known to be contaminated with pesticides and evaluate their ability to degrade two important pesticides, chlorantraniliprole (CAP), and flubendiamide (FBD). In our study, six isolates showed maximum growth in the presence of CAP and FBD in the growth media as a sole carbon source. The isolates were purified and then identified by biochemical and morphological tests, MALD-TOF-MS, and 16S rRNA techniques, as Bacillus subtilis subsp. subtilis AZFS3, Bacillus pumilus AZFS5, Bacillus mojavensis AZFS15, Bacillus paramycoides AZFS18, Pseudomonas aeruginosa KZFS4, and Alcaligenes aquatilis KZFS11. The degradation ability of studied bacterial strains against pesticides was estimated under different conditions (temperatures, pH, salt, and incubation time). The results reveal that the optimal conditions for all bacterial strains’ growth were 30−35 °C, pH 7.0, 0.0−0.5% NaCl, and an incubation period of 11 days a... [more]

Utilization of bioenergy with carbon capture can realize carbon-negative syngas production. The quadruple fluidized bed gasifier (QFBG) integrates a chemical looping oxygen generation process and a dual fluidized bed gasifier with limestone as bed material. It is one promising device that can convert biomass to H2-rich syngas whilst capturing CO2 with little energy penalty. However, experimental or numerical simulation of QFBG is rarely reported on due to its complex structure, hindering the further commercialization and deployment of QFBG. In this work, a new computational fluid dynamics (CFD) solver is proposed to predict the complex physicochemical processes in QFBG based on the multi-phase particle in cell (MPPIC) methodology with the assistance of the open source software, OpenFOAM. The solver is first validated against experimental data in terms of hydrodynamics and reaction kinetics. Then, the solver is used to investigate the QFBG property. It is found that the QFBG can operate... [more]

The outlet liquid material concentration is a key production indicator to evaluate the evaporation quality and an important basis to adjust the evaporation operation parameters. However, the online concentration analyzer has strict installation conditions and high prices, and it is difficult to obtain the liquid material concentration in time. Usually, the field works perform imprecise operations according to the time delay information. In addition, the process data contain errors, which affects the accuracy and timeliness of process optimization and control. Therefore, a hybrid prediction model of concentration based on data reconciliation is presented in this paper. First, to obtain the high-quality process data, the data reconciliation method is applied for preprocessing. Moreover, the process mechanistic model is constructed by utilizing the process knowledge and the balance principle. Taking into account the volatility and nonlinearity characteristics, a data-driven model based on... [more]

The last-mile logistics is regarded as one of the least efficient, most expensive, and polluting part of the entire supply chain and has a significant impact and consequences on sustainable delivery operations. The leading business model in e-commerce called Attended Home Delivery is the most expensive and demanding when a short delivery window is mutually agreed upon with the customer, decreasing possible optimizing flexibility. On the other hand, last-mile logistics is changing as decisions should be made in real time. This paper is focused on the proposed solution of sustainability opportunities in Attended Home Delivery, where we use a new approach to achieve more sustainable deliveries with machine learning forecasts based on real-time data, different dynamic route planning algorithms, tracking logistics events, fleet capacities and other relevant data. The developed model proposes to influence customers to choose a more sustainable delivery time window with important sustainabili... [more]

Bisphenol A, bisphenol S, and fluconazole are environmental contaminants widely found in surface waters because of their extensive usage and low biodegradability. Therefore, other methods are often considered for the removal of these compounds. The present study aims at their photodegradation with the use of UV light and three different catalysts, ZnO, TiO2, and Ag-TiO2. The results obtained show that photocatalytic removal of these compounds is also problematic and the use of catalysts, such as ZnO and TiO2, at increasing concentrations mostly leads to lower degradation of the tested compounds. The modification of TiO2 with silver increases the degradation of both bisphenols up to 100%, which was achieved in 60 min by bisphenol A and in as little as 10 min by bisphenol S. Nevertheless, the degradation of fluconazole remained at the same level, not exceeding 70% in 60 min, i.e., still much lower than expected. In addition, the degradation products of bisphenols show the hydroxylation a... [more]

Due to the fitted structure of fuzzy logic, neural networks and evolutionary computing, neuro-fuzzy systems, evolutionary-fuzzy systems, and evolutionary neural systems, we can study computational intelligence [...]