In order to further understand the complex spatial distribution caused by the extremely strong heterogeneity of buried hill reservoirs, this paper proposes a new method for predicting the development pattern of buried hill reservoirs based on the traditional pre-drilling prediction and post-drilling evaluation methods that mainly rely on seismic, logging, and core data, which are difficult to meet the timeliness and accuracy of drilling operations. Firstly, the box method and normalization formula are used to process and normalize the abnormal data of element logging and engineering logging, and then the stepwise regression analysis method is used to optimize the sensitive parameters of element logging and engineering logging. The Light Gradient Boosting Machine (LightGBM) algorithm, deep neural network (DNN), and support vector machine (SVM) are used to establish a new method for predicting the development pattern of buried hill reservoirs. Lastly, a comprehensive evaluation index F1... [more]

This article presents the results of cyanide leaching of gold-containing concentrate using the trichlorocyanuric acid (TCCA) oxidizer. Gold-containing concentrate was obtained from a gold tailings sample from a gold recovery factory (GRF) in one of the deposits of Kazakhstan that have not previously been studied for concentrability. According to X-ray phase analysis and energy dispersive spectrometry (DSM) data, the main compounds in the tailings sample under study are pyrite FeS2, quartz SiO2, calcite CaCO3, albite NaAlSi3O8, muscovite KAl2Si3AlO10(OH)8, dolomite CaMg(CO3)2, and oxidized iron compounds. Microscopic studies of the concentrate have established the presence of ultrafine gold with sizes from Au 0.9 to 10.2 μm in pyrite. Obtaining the gold-containing concentrate with a gold content of 15.95 g/t is possible according to the enrichment scheme, which includes centrifugal separation, classification according to the fineness class −0.05 mm, additional grinding of hydrocyclone s... [more]

Due to its unique chemical structure, hydrogen energy inherently has a high calorific value without reinforcing global warming, so it is expected to be a promising alternative energy source in the future. In this work, we focus on nanoconfined hydrogen flow performance, a critical issue in terms of geological hydrogen storage. For nanopores where the pore scale is comparable to hydrogen’s molecular size, the impact on hydrogen molecules exerted by the pore surface cannot be neglected, leading to the molecules near the surface gaining mobility and slipping on the surface. Furthermore, hydrogen adsorption takes place in the nanopores, and the way the adsorption molecules move is completely different from the bulk molecules. Hence, the frequently applied Navier−Stokes equation, based on the no-slip boundary condition and overlooking the contribution of the adsorption molecules, fails to precisely predict the hydrogen flow capacity in nanopores. In this paper, hydrogen molecules are classi... [more]

Horizontal-well multi-cluster fracturing is one of the most important techniques for increasing the recovery rate in unconventional oil and gas reservoir development. However, under the influence of complex induced stress fields, the mechanism of interaction and propagation of fractures within each segment remains unclear. In this study, based on rock fracture criteria, combined with the boundary element displacement discontinuity method, a two-dimensional numerical simulation model of hydraulic fracturing crack propagation in a planar plane was established. Using this model, the interaction and propagation process of inter-cluster fractures under different fracturing sequences within horizontal well segments and the mechanism of induced stress field effects were analyzed. The influence mechanism of cluster spacing, fracture design length, and fracture internal pressure on the propagation morphology of inter-cluster fractures was also investigated. The research results indicate that, w... [more]

A wide range of gluten-free bakery products are already available on the market. However, they often have a low proportion of fiber and inferior sensory properties when compared to classic baked goods. The aim of this work was to evaluate the influence of the addition of different types of fiber and insect powder on selected organoleptic and nutritional properties of gluten-free bread and to reformulate a recipe for gluten-free bread. Twenty-four experimental samples were prepared with different types and percentages of fiber, either alone or in combination. Sensory analysis, instrumental texture analysis, and chemical analyses, including predicted glycemic index, were carried out. A total of 16 of the 24 fiber-enriched samples received an average or slightly above-average rating. The samples containing the fiber mixture without insect powder and the sample containing 9% flaxseed performed best in the overall evaluation. The combination of different types of plant fibers simultaneously... [more]

This paper presents a method to design a static output feedback active suspension controller for ride comfort improvement and motion sickness reduction in a real vehicle system. Full-state feedback controller has shown good performance for active suspension control. However, it requires a lot of states to be measured, which is very difficult in real vehicles. To avoid this problem, a static output feedback (SOF) controller is adopted in this paper. This controller requires only three sensor outputs, vertical velocity, roll and pitch rates, which are relatively easy to measure in real vehicles. Three types of SOF controller are proposed and optimized with linear quadratic optimal control and the simulation optimization method. Two of these controllers have only three gains to be tuned, which are much smaller than those of full-state feedback. To validate the performance of the proposed SOF controllers, a simulation is carried out on a vehicle simulation package. From the results, the pr... [more]

Further exploitation of the residual oil underground in post-polymer flooded reservoirs is attractive and challenging. Microbial-enhanced oil recovery (MEOR) is a promising strategy to enhance the recovery of residual oil in post-polymer flooded reservoirs. Identifying and selectively activating indigenous microorganisms with oil displacement capabilities is an urgent requirement in the current design of efficient microbial-enhanced oil recovery technologies. This study combines high-throughput sequencing with functional network analysis to identify the core functional microbes within the reservoirs. Concurrently, it devises targeted activation strategies tailored to oligotrophic conditions through an analysis of environmental factor influences. The feasibility of these strategies is then validated through physical simulation experiments. With nutrient stimulation, the overall diversity of microorganisms decreases while the abundance of functional microorganisms increases. The core dis... [more]

The accurate calculation of the hotspot temperature of the cable intermediate joint can effectively guarantee the safe operation of the transmission and distribution network. This paper addresses the limitations of the current method of estimating hotspot temperature solely from surface temperature measurements. Specifically, we focus on a 110 kV single-core cable as our subject of study. We started by establishing a simulation model for the temperature field at the intermediate joint to generate data samples. Subsequently, the NCA (neighborhood component analysis) algorithm was employed to select the optimal measurement points on the cable’s surface. This allowed determination of the quantity and location of characteristic points. Finally, we developed a cascading inversion model, which consists of a radial inversion model and an axial inversion model, based on the extreme learning machine algorithm. The example results show that the mean squared error of hotspot temperature obtained... [more]

Shale oil and gas wells usually experience a rapid decline in production due to their extremely low permeability and strong heterogeneity. As a crucial technique to harness potential and elevate extraction rates in aged wells (formations), refracturing is increasingly employed within oil and gas reservoirs globally. At present, the selection processes for refracturing, both of wells and layers, are somewhat subjective and necessitate considerable field data. However, the status of fracturing technology is difficult to control precisely, and the difference in construction effects is large. In this paper, well selection, formation selection, and the fracturing technology of shale oil and gas refracturing are deeply analyzed, and the technological status and main technical direction of refracturing technology at home and abroad are analyzed and summarized. The applicability, application potential, and main technical challenges of existing technology for different wells are discussed, comb... [more]

The contamination of the water bodies by diesel oil (DO) and its water-soluble fraction (WSF) represents one of the most challenging tasks in the management of polluted water streams. This paper contains data related to the synthesis and characteristics of the plum stone biochar material (PmS-B), which was made from waste plum stones (PmS), along with its possible application in the sorption of the WSF of DO from contaminated water. Techniques applied in sample characterisation and comparisons were: Elemental Organic Analysis (EOA), Scanning Electron Microscopy−Energy Dispersive X-ray Spectroscopy (SEM-EDX), Fourier Transform Infrared Spectroscopy (FTIR), pH (pHsus) and point of zero charge (pHpzc). In order to increase the overall efficiency of the removal process, sorption and bioremediation were subsequently combined. Firstly, PmS-B was used as a sorbent of WSF, and then the remaining solution was additionally treated with a specific consortium of microorganisms. After the first tre... [more]

The presented review is focused on a brief overview of the scientific works on the use of sheep wool outside the textile industry that were published in recent years. The focus of the information is the on construction industry, which is a significant consumer of heat- and sound-insulating materials. With its properties, sheep wool can compete very well with insulators made from non-renewable resources. Other building elements can also be combined with wool, as long as they are used in appropriate conditions. Due to its chemical and physical structure, wool is extremely suitable for the adsorption removal of pollutants from the living and working environment, in native or modified form. Wool can also be used in recycling processes. However, each application must be preceded by an investigation of the optimal conditions of the given process, which offers researchers inspiration and interesting topics for research.

In this paper, computational fluid dynamics (CFD) numerical simulation is employed to analyze and discuss the effect of obstacle gradient on the flame propagation characteristics of premixed hydrogen/air in a closed chamber. With a constant overall volume of obstacles, the obstacle blocking rate gradient is set at +0.125, 0, and −0.125, respectively. The study focuses on the evolution of the flame structure, propagation speed, the dynamic process of overpressure, and the coupled flame−flow field. The results demonstrate that the flame front consistently maintains a jet flame as the obstacle gradient increases, with the wrinkles on the flame front becoming increasingly pronounced. When the blocking rate gradients are +0.125, 0, and −0.125, the corresponding maximum flame propagation speeds are measured at 412 m/s, 344 m/s, and 372 m/s, respectively, indicating that the obstacle gradient indeed increases the flame propagation speed. Moreover, the distribution of pressure is closely relat... [more]

Polystyrene plastics present significant environmental and human health threats due to their poor recyclability and degradability. However, leveraging their properties to enhance material performance stands out as one of the most effective strategies for mitigating these issues. Here, we have employed recycled expanded polystyrene plastics to manufacture metal−organic framework/expanded polystyrene plastic composites (MOF@EPP) using an adverse solvent precipitation method. This method simultaneously recycles EPPs and safeguards moisture-sensitive MOFs. Due to the exceptional hydrophobic properties of EPPs, HKUST−1@EPP can maintain structural integrity even when immersed in water for 30 days. This method is applicable to other moisture-sensitive MOFs, such as MOF−74(Zn) and MIL−53(Al). The HKUST−1@EPP composite also exhibits desirable heterogeneous catalytic activity in the Knoevenagel condensation reaction between benzaldehyde and acrylonitrile. The conversion rate can reach 94.9% with... [more]

Carbon sequestration through CO2 injection into a formation is an effective strategy for reducing greenhouse gas emissions. In this study, a one-dimensional long reactor was constructed to simulate the CO2 injection process under various sediment temperatures, pressures, and flow rates. The formation of CO2 hydrate and the resulting blockages were investigated in detail through a series of indoor experiments. Due to the increasing driving force for CO2 hydrate formation, reducing sediment temperature and increasing sediment pressure can cause hydrate blockage to form near the injection end, leading to an increase in CO2 injection pressure and a reduction in the storage range. Furthermore, CO2 injection rate has a substantial impact on the pattern of hydrate blockage. A lower injection rate facilitates full contact between CO2 gas and pore water, which helps to increase the formation and blockage degree of CO2 hydrates, thereby decreasing the amount of CO2 injection. The experimental in... [more]

Industrial boilers cause significant energy wastage that could be mitigated with oxy-fuel combustion versus traditional air combustion. Despite several feasibility studies on oxy-fuel burners, they are widely avoided in industry due to major infrastructural challenges. This study measured the performance and heat transfer characteristics of each component in a 0.5 MW fire tube gas boiler after retrofitting it with an oxy-fuel burner. Comparisons were drawn across three combustion modes—air combustion, oxy-fuel combustion, and oxy-fuel flue gas recirculation (FGR). The Dittus−Boelter equation was employed to predict heat transfer in the fire tube for all combustion modes at full load (100%). Heat transfer in the latent heat section of the economizer was measured and compared with predictions using the Zukauskas equation. With this retrofit, oxy-fuel combustion improved the thermal efficiency by about 3−4%. In oxy-fuel combustion, the flow rate of exhaust gas decreased. When integrated i... [more]

The implementation of CO2 huff-n-puff in unconventional oil reservoirs represents a green development technology that integrates oil recovery and carbon storage, emphasizing both efficiency and environmental protection. A rational well selection method is crucial for the success of CO2 huff-n-puff development. This paper initially identifies eight parameters that influence the effectiveness of CO2 huff-n-puff development and conducts a systematic analysis of the impact of each factor on development effectiveness. A set of factors for well selection decisions is established with seven successful CO2 huff-n-puff cases. Subsequently, the influencing factors are classified into positive, inverse, and moderate indicators. By using an exponential formulation, a method for calculating membership degrees is calculated to accurately represent the nonlinearity of each parameter’s influence on development, resulting in a dimensionless fuzzy matrix. Furthermore, with the oil exchange ratio serving... [more]

Continuous monitoring of structural health is essential for the timely detection of damage and avoidance of structural failure. Guided-wave ultrasonic testing (GWUT) assesses structural damages by correlating its sensitive features with the damage parameter of interest. However, few or no studies have been performed on the detection and influence of debris-filled damage on GWUT under environmental conditions. This paper used the pitch−catch technique of GWUT, signal cross-correlation, statistical root mean square (RMS) and root mean square deviation (RMSD) to study the combined influence of varying debris-filled damage percentages and temperatures on damage detection. Through experimental result analysis, a predictive model with an R2 of about 78% and RMSE values of about 7.5×10−5 was established. When validated, the model proved effective, with a comparable relative error of less than 10%.

Cocoa bean shell (CBS), a by-product from the chocolate industry, is an interesting source of bioactive compounds. In this work, the effects of time and pH on the hydrothermal hydrolysis of CBS were evaluated with the aim of maximizing the extraction of antioxidant and functional compounds from this biomass. In general, all treatments tested led to improvements in the extraction of bioactive compounds compared to untreated samples. The maximum values for antioxidant activity (187 µmol TE/g CBS dw) and phenolic compounds (14.5 mg GAE/g CBS dw) were obtained when CBS was treated at pH 4 for 10 min. In addition, maximum amounts of flavonoids (10.1 mg CE/g CBS dw), tannins (6.5 mg CE/g CBS dw) and methylxanthines (9 mg/g CBS dw) were obtained under mild pH conditions (4−5). It is noteworthy that these values are higher than those reported in the literature for other vegetable substrates, highlighting the potential of CBS to be valorized as a source of different value-adding products.

Magnetic nanofluids, also referred to as ferromagnetic particle levitation systems, are materials with highly responsive magnetic properties. Due to their magnetic responsiveness, excellent controllability, favorable thermal characteristics, and versatility, magnetic nanofluids have sparked considerable interest in both industrial manufacturing and scientific research. Magnetic nanofluids have been used and developed in diverse areas such as materials science, physics, chemistry and engineering due to their remarkable characteristics such as rapid magnetic reaction, elastic flow capacities, and tunable thermal and optical properties. This paper provides a full and in-depth introduction to the diverse uses of ferrofluids including material fabrication, fluid droplet manipulation, and biomedicine for the power and machinery sectors. As a result, magnetic nanofluids have shown promising applications and have provided innovative ideas for multidisciplinary research in biology, chemistry, p... [more]

An accurate wind shear model is an important prerequisite in extrapolating the wind resource from lower heights to the increasing hub height of wind turbines. Based on the 1-year dataset (collected in 2014) consisting of 15-minute intervals collected at heights of 2, 10, 50, 100, and 150 m on an anemometer tower in northern China, the present study focuses on the time-varying relationship between the wind shear coefficient (WSC) and atmospheric stability and proposes a wind shear model considering atmospheric stability. Through the relationship between Monin−Obukhov (M-O) length and gradient Richardson number, the M-O length is directly calculated by wind data, and the WSC is calculated by combining the Panofsky and Dutton (PD) models, which enhances the engineering practicability of the model. Then, the performance of the model is quantified and compared with two alternative methods: the use of annual average WSC and the use of stability change WSC extrapolation. The analysis demonstr... [more]

The manufacturing and energy industry are typical complex large systems which cover a long cycle such as design [...]

In this paper, the possibility of combining electrocoagulation (EC), ultrasound, and the addition of zeolite for wastewater treatment was investigated for the first time. The following combinations of hybrid processes were tested: electrocoagulation with zeolite (ECZ), simultaneous electrocoagulation with zeolite and ultrasound (ECZ+US), and two-stage electrocoagulation with zeolite and ultrasound (US+Z - EC), carried out with three different electrode materials. The results show that the simultaneous assistance of ultrasound in the ECZ leads to a lower increase in pH, while the temperature increase is higher. Regarding the COD, the assistance of ultrasound is only useful for Zn electrodes in the two-stage US+Z - EC, while the reduction in voltage consumption occurs for Fe and Al electrodes. Ultrasonic assistance caused more damage to the anodes, but anode consumption was reduced for Al and Zn electrodes. The total amount of zeolite that can be recovered is between 55−97%, and recovery... [more]

To address the issue of local optima encountered during the multi-objective optimization process with the Non-dominated Sorting Genetic Algorithm II (NSGA-II) algorithm, this paper introduces an enhanced version of the NSGA-II. This improved NSGA-II incorporates polynomial and simulated binary crossover operators into the genetic algorithm’s crossover phase to refine its performance. For evaluation purposes, the classic ZDT benchmark functions are employed. The findings reveal that the enhanced NSGA-II algorithm achieves higher convergence accuracy and surpasses the performance of the original NSGA-II algorithm. When applied to the machining of the high-hardness material 20MnCrTi, four algorithms were utilized: the improved NSGA-II, the conventional NSGA-II, NSGA-III, and MOEA/D. The experimental outcomes show that the improved NSGA-II algorithm delivers a more optimal combination of process parameters, effectively enhancing the workpiece’s surface roughness and material removal rate.... [more]

Sub-critical water is an environment-friendly solvent. It is widely used for the extraction of various organic compounds. It can be used to dissolve and transport organic matter in oil shale. In this study, the conversion of oil shale was synergistically catalyzed by the addition of Fe or Ni to the Fe inherent in samples under sub-critical water conditions. Oil shale can be converted to gas, oil and residues of oil. Thermogravimetric (TG) analysis results presented that the weight loss of raw oil shale was up to 15.85%. After sub-critical water extraction, the weight loss rate of the residues was reduced to 8.41%. With the application of a metal catalyst, Fe or Ni, the weight loss of residues was further reduced to 7.43% and 6.57%, respectively. According to DTG curves, it was found that there were two weight-loss rate peaks. The decomposition process of kerogen in oil shale could be divided into two cracking processes. One is decomposed at a high velocity at around 420 °C, and another... [more]

Industrial pure zirconium plays an essential role as a structural material in the nuclear energy sector. Understanding the deformation mechanisms is crucial for effectively managing the plasticity and texture evolution of industrial pure zirconium. In the present study, the texture and microstructure evolution of industrial pure zirconium during the cold-rolling process have been characterized by XRD, EBSD, and TEM. The influences of various twins on texture evolution have also been simulated by the reaction stress model. The effects of slip and twinning on the deformation behavior and texture evolution have been discussed based on crystallographic and experimental considerations. Cold rolling yields a typical bimodal texture, resulting in the preferential //RD orientation. The activation of the deformation mechanisms during cold rolling follows the sequential trend of slip, twinning, local slip. Experimental characterization and reaction stress simulation illustrate that T1 twins domi... [more]