Numerical simulation is used to carry out research on the swirl flow transportation of a hydrate in the pipeline under the condition of the whole rotation of the twist tape using DPM (discrete phase modeling) and RNG (renormalization group) k-ε. The influence of different twist tape parameters on the swirl number and concentration distribution of hydrate particles is analyzed. The structure parameters of the twist tape are optimized, based on the swirl efficiency evaluation parameters of a gas-solid two-phase pipeline. Finally, the twist tape is compared with different working conditions: the local rotation of twist tape and an ordinary pipeline. The results show that the areas of a high concentration of particles are near the twist tapes, and the concentration of particles on the leeward side of the twist tapes is higher than that on the windward side. The minimum concentration area at the axial position gradually increases with the increase of the flow distance, and the hydrate parti... [more]

Prolonged development of ore deposits, ore beneficiation and metallurgical smelting of concentrates result in the accumulation of wastes, forming large-scale dumps and sludge ponds negatively affecting the environment and human health. The creation and introduction of industrial waste treatment technologies will make it possible to dispose of them with the production of valuable commercial products and improve the environmental situation. In a research article on chemical beneficiation with the subsequent gravitational beneficiation of chrome-containing slurry tailings of Donskoy Ore-Mining and Beneficiation Plant (DOMBP), which processes chrome ore of the Kempirsay deposit in the Republic of Kazakhstan, Aktobe region, having considerable stocks of such waste is presented. The chromium-containing slurry tailings were heat-treated at 1100 °C, sintered with ammonium sulfate, water and sulfuric acid in a defined ratio at 300 °C, and then the resulting sinter was leached with water at 90 °... [more]

In the process of fracturing construction in shale gas reservoirs, microseism is a common means and effective method to evaluate the fracturing effect, but it is not suitable for large-scale and large batches due to its high applicability conditions and cost. Therefore, a concise, fast and low-cost post-fracturing effect evaluation method is needed to evaluate the complexity of fractures formed by fracturing in shale gas reservoirs. In this paper, based on the basic theory of the G-function, the free variable μ was introduced to correct the filter loss coefficient with the participation of natural fractures, and thousands of G-function curves were plotted with fracturing data from hundreds of gas wells in the southern Fuling shale gas field in China. Through the feature analysis of the curve morphology, a G-function graphic template conforming to the block was established, which contains four types and eight morphologies. Four characteristic parameters in the G-function curve were sele... [more]

Protein structure prediction is one of the important aspects while dealing with critical diseases. An early prediction of protein folding helps in clinical diagnosis. In recent years, applications of metaheuristic algorithms have been substantially increased due to the fact that this problem is computationally complex and time-consuming. Metaheuristics are proven to be an adequate tool for dealing with complex problems with higher computational efficiency than conventional tools. The work presented in this paper is the development and testing of the Ingenious Crow Search Algorithm (ICSA). First, the algorithm is tested on standard mathematical functions with known properties. Then, the application of newly developed ICSA is explored on protein structure prediction. The efficacy of this algorithm is tested on a bench of artificial proteins and real proteins of medium length. The comparative analysis of the optimization performance is carried out with some of the leading variants of the... [more]

A sequencing batch reactor (SBR) inoculated with activated sludge and bioaugmented with a dye-decolorizing yeast strain—Yarrowia lipolytica (HOMOGST27AB) was assembled to form yeast-bioaugmented aerobic granular sludge (AGS). The bioaugmented AGS-SBR was operated for the treatment of synthetic saline wastewater (12 g L−1) intermittently fed with a reactive textile dye (Navy Everzol ED) at 25, 15, and 7.5 mg L−1. Dye degradation did not occur, although some dye adsorbed to the granules. AGS-SBR performance in removing carbon and nitrogen was good and was not affected by the dye addition. Bioaugmentation with the yeast Y. lipolytica (HOMOGST27AB) occurred with success, proved by sequencing samples from granules throughout the reactor operation. The AGS core microbiome gathered essentially microorganisms from the Proteobacteria and Bacteroidetes phyla. The microbial profile showed a dynamic microbiome established at Phase I of the operation, with a high decrease in the abundance of Ignavi... [more]

Sodium new houttuyfonate (SNH) is volatile oil extracted from Houttuynia cordata Thunb. Its molecular formula is C14H27O5SNa, and molecular weight is 330.41. It is a new anti-inflammatory drug that has been used clinically over recent years. In this work, the binding interaction simulation study on SNH and epidermal growth factor receptor-tyrosine kinase (EGFR-TK) was conducted. SNH demonstrated a good binding ability to EGFR-TK and formed hydrogen-bonds with Cys773, Asp776, and Tyr777. This indicated that SNH might play an antitumor role as a potential inhibitor of EGFR-TK. In vitro, after treatment with various doses of SNH for 48 h, the viability of MCF-7 cells was 100.0, 98.23, 83.45, 76.24, 68.53, and 32.24, respectively, accompanied by a concentration increase in SNH. Moreover, cell viability of 250 μg/mL group decreased by more than 30%. Meanwhile, SNH significantly decreased cell cloning ability, and the quantities of clones were 456, 283, 137, and 152 in different groups (0 μg... [more]

The use of multilateral wells is an important method to effectively develop complex oil reservoirs, and wellbore stability research of multilateral wells is of great importance. In the present study, the effects of formation fluids and rock damage were not taken into account by the wellbore stability model. Therefore, finite element analysis (FEA) software was used to establish a three-dimensional (3D) seepage-stress FEA model for the multilateral junctions. The model was used to analyze the wellbore stability of multilateral wells and study influences of wellbore parameters and drilling fluid density on wellbore stability at multilateral junctions. Simulation results show that the wellbore diameter insignificantly affects wellbore stability. When the angle between the main wellbore and branches enlarges to 45°, the equivalent plastic strain decreases by 0.0726, and the wellbores become more stable; when the angle is larger than or equal to 45°, the region prone to wellbore instability... [more]

While heating a seawater spiral shell (Euplica scripta), thermally induced aragonite−calcite (A−C) transformation occurred within the temperature region of multistep thermal dehydration. Here, the kinetic interplay between the A−C transformation and thermal dehydration was studied as a possible cause of the reduction in the A−C transformation temperatures. The kinetics of the A−C transformation was systematically investigated under isothermal conditions by powder X-ray diffractometry and under linear nonisothermal conditions by Fourier transform infrared spectroscopy. The thermal dehydration was characterized as a partially overlapping, three-step process by thermogravimetry−differential thermal analysis coupled with mass spectroscopy for the evolved gases. The A−C transformation occurred in the temperature range of the final part of the second dehydration step and the initial part of the third dehydration step. The kinetics of A−C transformation and thermal dehydration were characteri... [more]

In this work, an integrated multiscale simulation of magnetron sputtering epitaxy was conducted to study the effect of sputtering pressure on the surface micro-topography of sputtered Cu/Si films. Simulation results indicated that, as the sputtering pressure increased from 0.15 to 2 Pa, the peak energy of the incident energy distribution gradually decreased from 2 to 0.2 eV, which might be mainly due to the gradual decrease in the proportion of deposited Cu atoms whose energy ranged from 2 to 30 eV; the peak angle of the incident polar angle distribution increased from 25° to 35°, which might be attributed to the gradual thermalization of deposited Cu atoms; the growth mode of Cu film transformed from the two-dimensional layered mode to the Volmer-Weber mode. The transformation mechanism of growth mode was analyzed in detail. A comprehensive analysis of the simulation results indicated that incident energy ranging from 2 to 30 eV and incident angle between 10° and 35° might be conduciv... [more]

Brewer’s spent grain (BSG) as the major byproduct in the brewing industry is a promising feedstock to produce value-added products such as volatile fatty acids (VFAs). Synergistic ball mill−enzymatic hydrolysis (BM-EH) process is an environmentally friendly pretreatment method for lignocellulosic materials before bioprocessing. This study investigated the potential of raw and BM-EH pretreated BSG feedstocks to produce VFAs through a direct thermophilic anaerobic fermentation process without introducing a methanogen inhibitor. The highest VFA concentration of over 30 g/L was achieved under the high-solid loading fermentation (HS) of raw BSG. The synergistic BM-EH pretreatment helps to increase the cellulose conversion to 70%. Under conventional low TS fermentation conditions, compared to the controlled sample, prolonged pretreatment of the BSG substrate resulted in increased VFA yields from 0.25 to 0.33 g/gVS, and butyric acid became dominant instead of acetic acid.

The occurrence of hump instability in pump mode within a pump turbine poses a significant challenge to the safe and stable operation of Pumped Storage Power Plants (PSPP). To achieve more precise numerical simulations, this paper establishes a weakly compressible model of water based on the Tait equation. Using this model, it is discovered that the onset of hump instability is closely linked to an increase in hydraulic losses induced by stalled rotation within the diffuser. Then, a flow control approach employing water injection into the guide vanes of a pump turbine is proposed in order to suppress flow instabilities and optimize the hump region. The findings reveal that the water injection approach can mitigate hydraulic losses, suppress unstable structures, and diminish the pulsation amplitude within the diffuser, ultimately delaying the emergence of the hump region to lower flow mass conditions. This study is helpful in widening the range of the safe and stable operation of pump tu... [more]

Hydraulic fracturing was the main technology to achieve the economic development of conglomerate reservoirs, knowing that the hydraulic fracture propagation mode was of great significance for improving the development of conglomerate reservoirs. This paper proposed a new method to understand the hydraulic fracture behavior based on a hybrid finite-discrete element method. The simulation indicated that a complex fracture network was created near the wellbore in the studied conglomerate reservoir, and hydraulic fracture propagation around the gravel layer was the main failure mode when the hydraulic fracture reached the gravel layer. From the simulations, it was shown that under small differences in horizontal stress and tensile strength, the hydraulic fracture propagated more easily around the gravel layer, while it could cross the gravel under large differences in horizontal stress and tensile strength. Greater tensile strength differences can reduce the complexity of the fracture netw... [more]

has several medicinal uses, especially its leaves. Over 4000 years ago, Ayurvedic medicine used it for its therapeutic benefits. This study examined the biological activity of Neem crude extracts and green-chemically produced Ag-NPs. TPCs and TFCs were measured for polyphenolic burden in consecutive extracts. DPPH, ABTS, and FRAP experiments measured antioxidant and antimicrobial activity against seven strains of food-borne pathogenic bacteria and eight mycotoxigenic fungi. At 1000 μg/mL, ethanolic and aqueous extracts of Neem leaves had 80.10% and 69.41% in DPPH and 71.42% and 74.61% in ABTS assays for the antioxidant activity, compared to 93.58% for BHT. At 800 μg/mL, both extracts showed antioxidant activity with 57.52 and 57.87 μM in the FRAP assay, compared to 139.97 μM for Ascorbic acid. Both extracts demonstrated antimicrobial activity with 0.02 to 0.35 mg/mL as antibacterials, 0.03 to 2.17 mg/mL as antifungals, and 0.04 to 0.42 mg/mL as antibacterials. Compared to Neem crude ex... [more]

Global situations such as economic recovery after a pandemic, geopolitical instability, and future digital and energy transition are some of the drivers for the European Union (EU) to explore new and existing sources of raw materials. The Iberian Pyrite Belt in the southwest of the Iberian Peninsula (Spain and Portugal) hosts a great number of tailing deposits from centuries of mining operations. A unique tailings deposit has been studied and characterized. The similarities with other tailing deposits deeply studied suggested the presence of critical raw materials. Furthermore, a very gross reserves estimation was made. The characterization and reserves estimations were compared with the bibliography from mining companies who operated in the area decades ago and from the bibliography available at Fundación Riotinto. The presence of critical raw materials was confirmed, some of them in high concentrations. Moreover, a singular difference was found compared with other similar tailings st... [more]

Organic-rich mud rocks are being developed on a large scale worldwide, including in the Middle East. The Jurassic Tuwaiq Mountain Formation (TMF) in the Jafurah Basin is a potential world-class unconventional play. Based on a petrophysical evaluation of the Jafurah basin, the TMF exhibits exceptional and unconventional gas characteristics, such as a high total organic content (TOC) and low clay content. Additionally, the TMF is in the appropriate maturity window, indicating that it has reached the required level of thermal maturity to generate hydrocarbons. Plans for the development of the Jafurah unconventional field use multistage hydraulic fracturing technology. The elastic properties of the shale formation, particularly its Young’s modulus and Poisson’s ratio, dictate how the rock responds to stress and deformation. These properties strongly impact the growth of hydraulic fractures in shale formations. Without a comprehensive understanding of the elastic properties, predicting the... [more]

A soil depleted of its organic carbon content is typically destabilized, i.e., its capacity to maintain its microstructure intact under various stress conditions weakens, and consequently, landslides and mudflows can be triggered and propagated more easily. In a previous work, we showed with a rheological analysis that the removal of the sole water-soluble organic carbon “destabilized” the slurry very similarly to what occurs with the removal of the vast majority of soil organic carbon. In principle, the water-soluble organic carbon can be dissolved by rainfall, during which water can infiltrate the soil, eventually leaving it either by percolation or evaporation. These two processes are mimicked here with two different soil water wetting procedures. The stability of the treated (wetted) soils is studied with rheological and granulometric experiments. The former run on concentrated suspensions, while the latter run on very diluted ones. Despite this, the results agreed very well, indic... [more]

In this work, the enzymatic synthesis of pentyl acetate obtained from acetic acid and pentan-1-ol using the commercial immobilized lipase Lipozyme®435 was studied. Specifically, the effects of several variables of the process on the kinetics were shown, such as the initial concentration of the acetic acid, the alcohol/acid molar ratio, and the possible reuse of the enzyme, while other variables, such as temperature, agitation, and the enzyme/acid ratio were held constant. The kinetics were determined by assessing the acetic acid concentration throughout the reactive process. Experimental data were correlated with the rate equation consisting of a modified version of the Bi−Bi Ping-Pong mechanism. The results showed that when no hydrophobic solvents were used with the reagents in stoichiometric proportion, a high molar fraction of acetic acid (x0,acid ≈ 0.50) caused the loss of enzymatic activity, achieving a conversion of only 5%. However, when there was an excess of pentan-1-ol, the r... [more]

The conversion of renewable energy into hydrogen (H2) by power-to-gas technologies involving electrolysis is seen today as a key element in the transition to a sustainable energy sector. Wastewater treatment plants (WWTP) could be integrated into future green H2 networks as users of oxygen (O2) produced alongside H2 in water electrolysis. In WWTPs, O2 is required for biological treatment steps, e.g., in activated sludge (AS) systems. However, the production costs of electrolysis O2 should be competitive with those of conventional O2 production processes. In this study, mathematical models of a polymer electrolyte membrane electrolyser (PEME) plant and the WWTP of the Benchmark Simulation Model No. 2 (BSM2) were used to simulate electrolysis O2 supply to an AS system and estimate net costs of production (NCP) for produced O2 via a techno-economic assessment (TEA). Assuming that produced H2 is sold to a nearby industry, NCPs for O2 were calculated for two different PEME plant dimensions,... [more]

The initial excitation of interface crack of large-size ultra-thin chips is one of the most complicated technical challenges. To address this issue, the reversible fracture characteristics of a silicon-based chip (chip size: 1.025 mm × 0.4 mm × 0.15 mm) adhesive layer interface was examined by scanning electron microscope (SEM) tests, and the characteristics of a cohesive zone model (CZM) unit were obtained through peel testing. The fitting curve of the elastic bilinear model was in high agreement with the experimental data, with a correlation coefficient of 0.98. The maximum energy release rate required for stripping was GC = 10.3567 N/m. Subsequently, a cohesive mechanical model of large-size ultra-thin chip peeling was established, and the mechanical characteristics of crack initial excitation were analyzed. The findings revealed that the larger deflection peeling angle in the peeling process resulted in a smaller peeling force and energy release rate (ERR), which made the initial c... [more]

Magnetic CuFe2O4 powder obtained by sol−gel method and coupled photocatalysis was used to activate peroxydisulfate for tetracycline (TC) removal. A scanning electron microscope, X−ray diffraction Raman spectroscopy and FT−TR were used to characterize the catalysts. The degradation efficiency and stability of TC were highest under neutral conditions. The TC degradation rate reached 91.1% within 90 min. The removal rate of total organic carbon reaches 39.6% under optimal conditions. The unique electron transfer property of CuFe2O4 was utilized to achieve the synergistic effect of photocatalysis and persulfate oxidation. The main oxidizing substances involved in the decomposition were sulfate radicals and hydroxyl radicals, and the removal rate of over 84% could be maintained after five cycles of experiments.

The control of a permanent magnet synchronous motor (PMSM) without a position sensor based on a sliding-mode observer (SMO) algorithm has a serious jitter problem in the process of motor phase tracking. A second-order adaptive sliding-mode observer algorithm was proposed, and the ideas and principles of the second-order sliding-mode observer algorithm based on the super-twisting algorithm were elaborated. In particular, adaptive estimation with the introduction of back-electromotive force (EMF) was investigated, and the Lyapunov stability criterion was used to determine the convergence properties of the algorithm. The results showed that the second-order adaptive sliding-mode observer algorithm had better jitter suppression and a better phase tracking performance than the traditional sliding-mode observer algorithm. The experimental results showed that when the motor velocity was 800 r/min, the velocity error of the second-order adaptive sliding-mode observer algorithm was 0.57 r/min a... [more]

The simulated moving bed (SMB) is a well-established, fully continuous process for chromatographic separation of difficult tasks with overlapping peaks, but it is relatively complex. The 1-SMB, which uses only one column but includes residence time zones to preserve concentration profiles, is a simpler semi-continuous alternative. This work examines the possible design of these residence time zones. Simulation studies were conducted to investigate the dependence of process metrics, such as purity, yield, productivity, and eluent consumption, on fluid dynamics. No deterioration in purity was observed, and the other variables remained constant over a wide range of axial dispersion before decreasing sharply. Pilot-scale experiments were conducted with various devices, including coiled flow inverters, eluate recycling devices, packed columns, and tank arrangements, to validate possible apparatus implementations with fluid dynamic measurements. It was demonstrated that the 1-SMB offers simi... [more]

In the era of digitalization, the process industry is one of the sectors most affected by the need for change. The adoption of IoT-based intelligent monitoring systems for the collection of real-time measurements of energy and other essential operational variables, on one hand, makes it possible to accumulate big data useful for the company management to monitor the stability of the production process over time, and on the other hand, helps to develop predictive models that enable more efficient work and production. The OTTORTO project stems from the need of the FARRIS company to adapt its production line to agriculture 4.0 policies, responding to the higher goals of digitization and technological transition imposed at the national and EU level. The objectives of the current study are (i) to present an “ad hoc” customized intelligent and multi-parameter monitoring system to derive real-time temperature and humidity measurements inside the company’s industrial drying kilns; and (ii) to... [more]

Buildings consume large amounts of energy resources and emit considerable amounts of greenhouse gases, especially existing buildings that do not meet energy standards. Building retrofitting is considered one of the most promising and significant solutions to reduce energy consumption and greenhouse gas emissions. However, finding suitable energy efficiency measures for existing buildings is extremely difficult due to the existence of thousands of retrofit measures and the need to meet various objectives. In this paper, a multi-stage decision framework, including a multi-objective optimization model, and a ranking method are proposed to help decision-makers select the optimal energy efficiency measures. The multi-objective optimization model considers the economic and environmental objectives, expressed as the retrofit cost and energy consumption, respectively. The entropy weight ideal point ranking method, an evaluation and ranking method that combines the entropy weight method and ide... [more]

Thermal energy recovery systems have different candidates to mitigate CO2 emissions as recommended by the UN in its list of SDGs. One of these promising systems is thermal absorption transformers, which generally use lithium-water bromide as the working fluid. A Double Stage Heat Transformer (DSHT) is a thermal machine that allows the recovery of thermal energy at a higher temperature than it is supplied through the effect of steam absorption in a concentrated solution of lithium bromide. There are very precise thermodynamic models which allow us to calculate all the possible operating conditions of the DSHT. To perform the control of these systems, the use of Artificial Intelligence (AI) is proposed with two computational techniques—Fuzzy Logic (FL) and Artificial Neural Network (ANN)—to calculate in real-time the set of variables that maximize the product’s Gross Temperature Lift (GTL) and Coefficient of Performance (COP) in a DSHT. The values for Coefficient of Determination (R2), M... [more]