The boost of shale gas production in the last decade has reformed worldwide energy structure. The macroscale modeling of shale gas production becomes particularly important as the economic development of such resources relies on the deployment of expensive hydraulic fracturing and the reasonable planning of well schedules. A flood of literature was therefore published focused on accurately and efficiently simulating the production performance of shale gas and better accounting for the various geological features or flow mechanisms that control shale gas transport. In this regard, this paper presents a holistic review of the macroscopic modeling of gas transport in shale. The review is carried out from three important points of view, which are the modeling of the gas flow mechanisms, the representation of multiscale transport, and solution techniques for the mathematical models. Firstly, the importance of gas storage and flow mechanisms in shale is discussed, and the various theoretical... [more]

In recent years, the drilling technology applied to deep and ultra-deep formations has developed rapidly, but the drilling speed for hard formations is low. Therefore, it is very important to study the drilling methods for deep and hard strata. Particle pulsed jet drilling is a new drilling method based on particle jet impact drilling technology and high-pressure pulsed water jet impact drilling technology. In this paper, the mathematical models of the shear layer amplification coefficient and wave velocity are established based on a similar network theory, and the motion equations of a single particle and particle swarm are established according to the motion of particles in a pulsed jet environment. Then, based on the self-designed particle jet impact rock-breaking experimental platform, the numerical simulation results are compared, analyzed, and verified. The results show that the rock-breaking efficiency increases with the increase in the average velocity of the particle pulsed je... [more]

Pyrolysis is a promising technology used to recycle both the energy and chemicals in plastics. Three types of plastics, polyethylene plastic (PE), polypropylene plastic (PP) and polystyrene plastic (PS) were investigated using thermogravimetry−mass spectrometry (TG−MS) and reactive force field molecular dynamics (ReaxFF-MD) simulation. The thermogravimetric analysis showed that all three plastics lost weight during the pyrolysis in one step. The thermal decomposition stability is PS < PP < PE. The activation energies and reaction mechanism function of the three plastics were determined by the Kissinger and CR methods. Meanwhile, the ReaxFF-MD combined with density functional theory (DFT) was used to calculate the kinetics, as well as explore the pyrolysis mechanism. The calculated kinetic results agree well with the experimental methods. The common pyrolysis reaction process follows the dissociation sequence of the polymer to polymeric monomer and, then, to the gas molecules. Bas... [more]

Straw, which is characterized by its low cost, large quantity, and rich supply of biomass energy, is often converted into energy that can be utilized in industrial production through pyrolysis technology. This paper examines the pyrolysis experiments of four kinds of straw (rice, wheat, peanut, and corn) from the Henan Province of China, conducted in an air environment with varying temperature-rise rates. Based on the experimental results, an analysis was conducted on the effect of the rate of temperature rise on the degree of straw pyrolysis and the pyrolysis characteristics of each type of straw. The activation energies of the pyrolysis reactions were calculated utilizing the Kissinger−Akahira−Sunose (KAS), Flynn−Wall−Ozawa (FWO), and Starink methods. It was concluded that the pyrolysis process of all four types of straw could roughly be classified into three stages: dehydration and drying stage, volatile release stage, and carbonization stage. Among the four types of straw evaluated... [more]

The presence of a reasonable flowback system after fracturing is a necessary condition for the high production of shale gas wells. At present, the optimization of the flowback system lacks a relevant theoretical basis. Due to this lack, this study established a new method for evaluating the conductivity of artificial fractures in shale, which can quantitatively characterize the backflow, embedment, and fragmentation of proppant during the flowback process. Then, the mechanism of the stress sensitivity of artificial fractures on fracture conductivity during the flowback stage of the shale gas well was revealed by performing the artificial fracture conductivity evaluation experiment. The results show that a large amount of proppant migrates, and the fracture conductivity decreases rapidly in the early stage of flowback, and then the decline gradually slows down. When the effective stress is low, the proppant is mainly plastically deformed, and the degree of fragmentation and embedment is... [more]

The main obstacles to scaling up membrane distillation (MD) on a commercial level are membrane fouling and temperature polarization. Therefore, in this study, the significance of the pulsation feed flow phenomenon was used for membrane distillation (DCMD) polarization, and comparisons were made using steady-state feed flow. Two different Hertz and amplitudes of pulsation feed flow trends were used in DCMD using different sources of water, including distilled water, seawater, and wastewater. Compared to steady-state feed flow, the results revealed that flux was enhanced for seawater once the operating flow became turbulent, and it enhanced even more once the flow rate was increased and the turbulence flow was moved. For wastewater, pulsation in the feed flow had an impact on delaying the beginning of the flux decline point and enhancing the overall freshwater recovery. In both pulsation feed flows (1 and 2 Hertz), the results also revealed a deficiency in fouling and an improvement in t... [more]

Water alternating gas (WAG) flooding is a widely employed enhanced oil recovery method in various reservoirs worldwide. In this research, we will employ SiO2 nanofluid alternating with the CO2 injection method as a replacement for the conventional WAG process in oil flooding experiments. The conventional WAG method suffers from limitations in certain industrial applications, such as extended cycle times, susceptibility to water condensation and agglomeration, and ineffectiveness in low-permeability oil reservoirs, thus impeding the oil recovery factor. In order to solve these problems, this study introduces SiO2 nanofluid as a substitute medium and proposes a SiO2 nanofluid alternate CO2 flooding method to enhance oil recovery. Through the microcharacterization of SiO2 nanofluids, comprehensive evaluations of particle size, dispersibility, and emulsification performance were conducted. The experimental results revealed that both SiO2-I and SiO2-II nanoparticles exhibited uniform spheri... [more]

The primary objective of this study was to investigate the survival rate of three species of encapsulated bacteria (Propionibacterium acidipropionicici, Propionibacterium freudenreichii, and Propionibacterium thoenii) in model solutions designed to simulate the acidity levels found within the human gastrointestinal tract. The capsules were prepared by extrusion from gelatin and sodium alginate in a 1:1 ratio on a laboratory encapsulator. The use of gelatin and sodium alginate was found to provide optimum characteristics suitable for encapsulation of live bacteria. Three strains of Propionibacterium asidirgorionici, Propionibacterium freudenreichii, and Propionibacterium thoenii were subjected to in vitro assay to evaluate their probiotic potential. The final cell survival rate of P. freudenreichii was 105 CFU/mL, indicating that this probiotic is sensitive to acidic medium. The viability of encapsulated probiotics was studied in a model medium simulating the gastrointestinal tract. It... [more]

Background: Microglial cells are immune cells that operate within the central nervous system. Abnormally activated microglia cause neuroinflammation, which is linked with neurodegenerative disease. Previous research has revealed that Rumex crispus root extract exerts anti-inflammatory effects. However, it is not known whether Rumex crispus leaf extract (RLE) has anti-inflammatory effects on murine microglial cells, such as BV-2 cells. This study proposed to investigate the impact of RLE on inducing inflammation by LPS in BV-2 cells. Methods: LPS was used to induce inflammation in BV-2 cells, and then cell survival, changes in the levels of inflammation-related factors and pro-inflammatory cytokines, and NF-κB and MAPKs signaling pathway activity were evaluated in the presence or absence of RLE. Results: RLE treatment resulted in a reduction in nitric oxide (NO) production triggered by LPS without causing cytotoxic effects. In addition, both protein and mRNA expression levels of iNOS an... [more]

The global trend towards net-zero carbon emissions from burning fuels in combustion engines alerts us to the alternative role of biodiesel. The manufacturing cost of biodiesel hinders the fast development of various types of biofuels. Feedstock cost is one of the major determining factors of biodiesel cost and thus the extent of its competitiveness in the fuel market with other available alternative fuels or fossil fuels. Some low-cost feedstocks such as high-acid oil, which is produced from the acidifying processes of soybean soapstock, frequently contain high contents of free fatty acids (FFAs) and water. Hence, those feedstocks cannot be used to produce biodiesel through strong alkaline catalyst transesterification on an industrial scale. In contrast, the water can be converted to hydroxyl radicals to enhance the formation of esters from the dissociation of the FFA in a supercritical reacting tank. Hence, cheap high-acid oils containing high amounts of water and FFAs were used to pr... [more]

Municipal and industrial wastewater discharge is a longstanding environmental problem that pollutes water bodies, affecting both the landscape and human health. In the department of Sucre, Colombia, nearby urban sewage is discharged into the Arroyo Grande de la Sabana, and only Sincelejo city has a treatment system in place. Therefore, it is critical to identify effective treatment methods for removing contaminants from water. The objective of this study was to evaluate the efficiency of a constructed wetland (CW) with horizontal subsurface flow (HSSF) planted with Thalia geniculata for treating wastewater from the Arroyo Grande de la Sabana in Sucre, Colombia. The study investigated the effectiveness of a constructed wetland planted with Thalia geniculata for treating wastewater from the Arroyo Grande de la Sabana in Sucre, Colombia. Two different hydraulic retention times (HRTs) of 3 and 5 days were tested, and the plant population density was analyzed to determine the better adaptat... [more]

Despite that previous research exists, there is a need for further research on the quantitative aspects of this Nexus. Existing Water-Energy-Environment Nexus management tools and frameworks are based on indicators aiming to model the whole system, analyze the involved resources, and test potential management strategies. The environmental, social, and economic consequences of actions already taken and ongoing projects require important focus because of the strong relationship between water and energy supply, and that both are key issues for society’s development and sustainability. The present research focuses on the indicators that the Water-Energy-Environment Nexus tools and frameworks use to analyze the whole problem. Existing tools often require large amounts of data, becoming a time-consuming process that lowers the capacity to evaluate the political problems of high pollutants. With the aim of accelerating time evaluation, this research builds an indicator to rapidly evaluate the... [more]

Challenges associated with mesophilic digestate (MD) involve volume, odor, and pathogens, which effective post-digestion treatments can address. The efficiency of MD post-treatment can be enhanced by conditioning with ferric chloride (FeCl3), hydrogen peroxide (H2O2), and polymer. This study aimed to observe the effect of combined chemical conditioning on volume reduction, phosphorus (P) release, odor, and pathogen reduction potential for MD. MD was conditioned with polymer only, polymer and FeCl3 at pH adjusted to 8.0 with lime (Ca(OH)2), and a blend of polymer, FeCl3, and hydrogen peroxide (H2O2) at pH 8.0. The results show that adding all three chemicals improved post-treatment efficiency at 2.1 kg/t DS FeCl3, 2.1 kg/t DS polymer, and 600 mg/L H2O2 at pH 8.0, compared with polymer or dual conditioning. At the combined dose, cake solid content, centrate P removal, and odor reduction capability improved compared with raw MD by 20%, 99%, and 66%, respectively. Combined chemical treatme... [more]

According to QYResearch, a global market research firm, the global market size of secondary batteries is growing at an average annual rate of 8.1%, but fires and casualties continue to occur due to the lack of quality and reliability of secondary batteries. Therefore, improving the quality of secondary batteries is a major factor in determining a company’s competitive advantage. In particular, lead taps, which electrically connect the negative and positive electrodes of secondary batteries, are a key factor in determining the stability of the battery. Currently, the quality inspection of secondary battery lead tab manufacturers mostly consists of visual inspection after vision inspection with a rule-based algorithm, which has limitations on the types of defects that can be detected, and the inspection time is increasing due to overlapping inspections, which is directly related to productivity. Therefore, this study aims to automate the quality inspection of lead tabs of secondary batte... [more]

(comfrey) is a perennial herb native to West Asia and Europe. Its root extracts are commonly used as a natural remedy to treat muscle, joint, skin, and bone disorders, especially in Europe. However, more information is needed on the biomedical functions of comfrey leaves. This study’s sequencing results of internal transcribed spacer and trnL−trnF genes showed that plants purchased from the local market were comfrey and named S. officinale WL (WL). The suitable extraction conditions of the WL leaves with the highest extract yield and total phenols and flavonoid contents by microwave-assisted extraction were identified. The antioxidative and anti-inflammatory activities and possible molecular mechanism(s) of the WL leaf extract (WLE) were evaluated. Furthermore, the major component of WLE was identified as rosmarinic acid by HPLC. Results showed that the optimal extract condition was obtained with 750 W microwave power, 50 °C, 75% methanol, the solid-to-solvent ratio of 1:10, and 15 min... [more]

Supramolecular gels are physically cross-linked hydrogels formed by non-covalent interactions. The synthesis, structure optimization, property regulation, and application expansion of supramolecular gels has gradually become the research hotspot in the field of gel materials. According to the non-covalent interactions such as hydrophobic association and hydrogen bonding, the supramolecular gel prepared in this study has excellent rheological properties and adaptive filling and plugging properties, and can be used in the field of drilling fluid plugging. In this paper, the microstructure, rheological properties, temperature resistance, and plugging properties of supramolecular gels were studied and characterized in detail. The experimental findings demonstrated that when the strain was less than 10%, the supramolecular gel displayed an excellent linear viscoelastic region. The increase in strain weakens the rheological properties of supramolecular gel and reduces the elastic modulus of... [more]

Hydrogen-based fluidized bed direct reduction (H-FBDR) is an important and promising route for fossil-free ironmaking. In this study, to achieve the optimal operation state of energy use and exergy efficiency, the influences of the metallization process and the ratios of H2 injected on the energy and exergy flows in the H-FBDR process are studied. The results show that the thermodynamically designed two-stage reduction process (first: Fe2O3→FeO; second: FeO→Fe) requires a smaller H2 quantity than other metallization processes. According to the mass, energy, and exergy balance analyses, variations in the H2 consumption, exergy destruction, and energy/exergy losses of the overall system, iron ore preheater (F1), fluidized bed reactor system (R), heat exchanger (E), and gas preheater (F2) with different ratios of H2 injected (η) are derived. The total H2 consumption, total exergy destruction, and energy/exergy losses rise with increasing η, and sharp increases are observed from η = 1.3 to... [more]

Non-enzymatic glycation is a process, which can be best described as a significant posttranslational modification of various proteins. It emerges in hyperglycemic conditions and may have an impact on albumin stability as well as its activity and physical and chemical properties, essentially affecting all its physiological functions. The goal of this research was to answer the following questions: (i) how does the glycation of defatted human serum albumin by glucose−fructose syrup (GFS) alter its tertiary structure; (ii) does palmitic acid (PA), a component of palm oil, affect the in vitro glycation process and cause conformational changes of glycated albumin; and (iii) does PA inhibit the formation of Advanced Glycation End-Products (AGEs)? Therefore, in order to point out differences in the tertiary structure of macromolecules, the absorption and emission of fluorescence spectra and their second derivatives, excitation fluorescence and synchronous spectra, Red-Edge Excitation Shift (R... [more]

The wet oxidation of pharmaceutical sludge for the treatment and production of value-added materials was investigated. The experiments were carried out in a stainless-steel autoclave reactor with chemical synthetic pharmaceutical sludge. The highest removal rate of total suspended solids (90.1%) and volatile suspended solids (98.4%) was achieved at 260 °C for 60 min with an initial oxygen pressure of 0.8 MPa. Simultaneously, the total chemical oxygen demand removal rate (78.7%) and the soluble chemical oxygen demand removal rate (81.6%) were obtained. The volatile fatty acid concentration—including acetic acid, propanoic acid, isobutyric acid and isovaleric acid—increased to 4819 mg/L with pH 12.56, which indicated the possibility of improving the quality of wet oxidized sludge solution as a potential carbon source by adding reagents. Scanning electron microscopy images showed that the sludge became a loose porous structure after wet oxidation, which is beneficial for dewatering perfor... [more]

In natural gas exploitation, foam drainage, corrosion inhibition and hydrate inhibition of wellbore fluid are conventional operations. However, there is often a problem where multiple chemical agents cannot be effectively used together and can only be used separately, resulting in complex production processes. In this study, the final integrated formulation was determined: 0.1% sodium alpha-olefin sulfonate (AOST) + 0.3% dodecyl dimethyl betaine (BS-12) + 0.3% sodium lignosulfonate + 0.5% hydrazine hydrate. The minimum tension of the integrated agent could be reduced to 23.5 mN/m. The initial foaming height of the integrated agent was 21.5 cm at 65 °C, the liquid-carrying capacity was 143 mL, and the liquid-carrying rate reached 71.5%. The maximum corrosion depth also decreased from 11.52 µm without the addition of hydrazine hydrate, gradually decreasing to 5.24 µm as the concentration of hydrazine hydrate increased. After adding an integrated agent, the growth rate of hydrates was slo... [more]

The record photovoltaic performance of perovskite solar cells is constantly increasing, reaching 26% currently. However, there is a crucial need for the development of simple architectures that are compatible with large-scale industrialization and possess adequate stability. The aim of the work presented here is to compare the efficiency of glass−glass and glass−backsheet encapsulations for carbon-based perovskite solar cell application, which possesses a great potential for industrialization. This was conducted by first separating the relative effects of humidity and heat. A time evolution of the macroscopic power conversion efficiency (PCE) was performed, together with specific characterizations in order to scout the origin of flaws and degradations. A significant contribution of the paper is the identification of both TiO2 and carbon layers as barriers against moisture permeation, which inhibit moisture paths through the interfaces. This is the origin of the equivalent durability of... [more]

An extremely important issue in quality management is monitoring and diagnosing processes, and, subsequently, supervising them using so-called control charts. In typical production processes, charts with constant parameters are commonly used, such as x-R, x-s, CUSUM, EWMA and others, which, in most cases, are effective tools for process stability evaluation. Charts considered untypical (in statistical process control) are those with variable sample sizes, variable sampling intervals and/or variable control limits. Such charts are used when process analysis based on standard, well-known charts may lead to serious errors. Modern control charts are a response to the requirements of Industry 4.0 and are an excellent tool for supervising production processes. Their use together with Cp and Cpk indices and other process capability indices is a starting point for process improvement. The methodology of nonstandard charts is inadequately recognized and rarely used in practice. The theory of th... [more]

Yttria-stabilized zirconia (YSZ), a thermal barrier coating material characterized by low thermal conductivity, is typically deposited via electron beam-physical vapor deposition. Notably, oxygen depletion occurs during this process, causing color changes in YSZ. Therefore, YSZ is speculated to undergo phase transformation during this process, which demands careful consideration owing to its effect on the life of thermal coatings. To study this phenomenon, bulk samples were prepared, subjected to vacuum heat treatment to induce oxygen depletion, and followed by oxidative heat treatment. Experimental results showed that the color of the samples changed to black after the vacuum heat treatment and to a lighter color after the oxidative heat treatment. In addition, X-ray diffraction and Raman analyses were performed. The monoclinic phase formation was confirmed during the vacuum heat treatment; however, it disappeared after the oxidation heat treatment. The coating obtained in a high vacu... [more]

Hay and straw are commonly used materials in agriculture. They are organic materials and, therefore, flammable. This article examines the behaviour of hay and straw when exposed to radiant heat. The objective of this study is to experimentally determine the ignition temperature of hay and straw under the influence of radiant heat. This research investigates the effects of sample type (hay and straw) and sample quantity on the thermal degradation process, temperature increase within the samples, and ignition temperature of the samples as a function of time. The ignition temperature of hay was determined to be higher (407 °C) compared to straw (380 °C).

Paraxanthine (PX), a major metabolite of caffeine, a protective agent against Alzheimer’s and Parkinson’s disease, and a promising drug for the treatment of post-COVID 2019 anosmia and ageusia, has been studied in the solid state and protein−ligand complex. Partial disorder in PX, caused by the methyl group at the N(7) position, has been modelled and discussed. The relationship between the unusual structural disorder and the propensity to form a specific system of non-covalent bonds was analyzed. Three 1H-14N NMR-NQR (nuclear magnetic resonance−nuclear quadrupole resonance) experimental techniques were used, namely multiple frequency sweeps, Larmor frequency scanning, and the two-frequency irradiation, followed by solid-state computational modelling (density functional theory, supplemented by quantum theory of atoms in molecules, 3D Hirshfeld surfaces, and reduced density gradient), and molecular docking approaches. New quantitative methods for estimating changes in the global pattern... [more]