Search Results (7,333)

Phenanthrenes, which are polycyclic aromatic hydrocarbons comprising three benzene rings, exhibit a diverse range of functions. These compounds are utilized in the synthesis of resins, plant growth hormones, reducing dyes, tannins and other products. Notably, phenanthrenes possess significant pharmacological properties, including anti-tumor, anti-inflammatory and antioxidant activities, offering broad prospects for development, particularly in the fields of medicine and health. Interestingly, although aristolochic acid (AA) is a potent carcinogen, its lactam analogs can kill cancer cells and exhibit therapeutic effects against cancer. This provides a promising strategy for the toxicity-effect transformation of phenanthrenes. In this paper, we reviewed 137 articles to systematically review the anti-tumor potential and toxic effects of natural phenanthrenes isolated from the 19th century to the present, thus offering references and laying a foundation for their further research, development and utilization. Full article

Accurately predicting the genesis and distribution of reservoir pressure is essential for comprehending the distribution of oil and gas reservoirs while mitigating drilling risks. In the Qiongzhusi Formation of the Sichuan Basin, overpressure has developed, leading to high production levels in several wells. However, the distribution and causal mechanism of overpressure within the Qiongzhusi Formation remain unclear at present. This study utilizes logging data from representative drilling wells to identify the causes of overpressure in the Qiongzhusi Formation and predict the characteristics of pressure distribution. The results indicate that the pressure coefficient of the Qiongzhusi Formation ranges from 1.01 to 2.05 and increases with burial depth. The overpressure in the Qiongzhusi Formation is attributed to fluid expansion, disequilibrium compaction, and pressure transmission. The contribution of disequilibrium compaction to pressure is 9.44 MPa, while hydrocarbon generation from organic matter contributes 82.66 MPa, and pressure transmission contributes 37.98 MPa. Additionally, the uplift erosion unloading effect and geothermal decline result in pressure reductions of approximately 26.68 MPa and 56.56 MPa, respectively. This study systematically elucidates the causes and distribution of overpressure in the Qiongzhusi Formation, providing valuable insights for subsequent exploration and development of shale gas in this formation. Full article

The pressure on the environment from wastewater has been increasing in line with industrialization and urbanization, thus calling for better and eco-friendly solutions for wastewater treatment. Extremophilic microorganisms, which can grow in extreme conditions including high salinity, acidity, and temperature, can be applied in wastewater bioremediation. This review assesses the various functions of extremophiles, halophiles, thermophiles, alkaliphiles, and acidophiles in the treatment of organic and inorganic pollutants. They are capable of catabolizing a wide range of hazardous chemicals, such as polycyclic aromatic hydrocarbons, phenolic compounds, and heavy metals. Moreover, extremophilic microalgae, like Galdieria sulphuraria, have been effective in nutrient removal, biosorption of heavy metals, and pollutant conversion into valuable biomass. This dual-functioning, therefore, helps not only in wastewater treatment but also in the production of biofuel and biofertilizer, making the process cost-effective. The use of extremophiles in biofilm reactors improves pollutant removal, with less energy input. Extremophilic microorganisms can, therefore, be used to revolutionize wastewater management by providing green solutions to current treatment approaches. This review discusses the existing drawbacks of wastewater treatment along with the additional requirements needed to enhance the capability of bioremediation and potential future research. Full article

Orientation tools in borehole imaging logs acquire magnetic information that is currently used for spatial and geographical orientation of the images. We propose to use this magnetic field information to estimate both magnetic susceptibility and remanent magnetization of rocks inside wells. Measurements of these magnetic parameters are not often available in hydrocarbon exploration to support forward modeling of magnetic data, an interpretation tool that has played important role in the exploration risk reduction in the Pre-Salt prospects of Campos Basin, Brazil. The acquired magnetic data requires corrections for tool rotation and diurnal variation of the Earth’s magnetic field before calculation. Then, using a set of simple equations and reasonable assumptions we were able to estimate the magnetic susceptibility of carbonates and basalts, as well as the remanent magnetization of the basalts, from a Pre-Salt well in Campos Basin. When compared to susceptibility values measured in laboratory for the same rock interval, our results show a significant match. This promising result shows the importance of our methodology in providing reliable information that can minimize uncertainties in forward modeling of magnetic data, which contributes to reduction of hydrocarbon exploration risks. Given that direct susceptibility and remanence measurements require oriented samples, a complex and expensive operation in wells, our results offer this rock information without any extra costs since imaging logs are commonly acquired in exploration wells. Besides its use in hydrocarbon exploration, our methodology can be applied to mineral exploration where magnetic susceptibility is an important property for rock identification. Full article

Siliceous minerals with the property of resistance to diagenetic alteration precipitate during the migration of hydrothermal fluids through strike-slip faults and the interaction of these fluids with host rocks during fault activity. Based on petrological analyses and U-Pb dating of siliceous minerals, the stages of strike-slip faulting of the ultra-deep-burial Ordovician in the Fuman oilfield were subdivided and their evolutionary process was discussed in combination with seismic interpretation. The results reveal the following: (1) the strike-slip faults contain hydrothermal siliceous minerals, including cryptocrystalline silica, crystalline silica, and radial silica. (2) Based on the twelve U-Pb ages of siliceous minerals (ranging from 458 ± 78 Ma to 174 ± 35 Ma) and five U-Pb ages of calcite, the activity of the strike-slip faults was divided into six stages: the Middle Caledonian, Late Caledonian, Early Hercynian, Middle Hercynian, Late Hercynian, and Yanshanian, corresponding to twelve siliceous U-Pb ages ranging from 458 ± 78 Ma to 174 ± 35 Ma, and five calcitic U-Pb ages. The Late Caledonian and Early Hercynian were the main periods of strike-slip fault activity, while the Late Hercynian period marked the final period of the fault system. (3) Later-stage faults inherited and developed from pre-existing faults. Steep linear strike-slip faults formed during the Middle and Late Caledonian movements. During the Late Hercynian and Yanshanian movements, mid-shallow faults, branch faults, and shallow echelon faults developed on the foundation of these linear faults. The methods and results of this study can guide future hydrocarbon exploration in the Fuman oilfield and can be applied to areas with similar tectonic backgrounds. Full article

Power generation is an important part of air vehicle energy management when developing long-endurance and reusable hypersonic aircraft. In order to utilize an air turbine power generation system on board, fuel-based rotating cooling has been researched to cool the turbine’s rotor blades. For fuel-cooling air turbines, each blade corresponds to a separate cooling channel. All the separate cooling channels cross together and form a distributary cavity and a confluence cavity in the center of the disk. In order to determine the flow characteristics in the distributary and confluence cavities, computational fluid dynamics (CFD) simulations using the shear–stress–transport turbulence model were carried out under the conditions of different rotating speeds and different mass flow rates. The results showed great differences between non-rotating flow and rotating flow conditions in the distributary and confluence cavities. The flow in the distributary and confluence cavities has rotational velocity, with obvious layering distribution regularity. Moreover, a high-speed rotational flow surface is formed in the confluence cavity of the original structure, due to the combined functions of centrifugal force, inertia, and the Coriolis force. Great pressure loss occurs when fluid passes through the high-speed rotational flow surface. This pressure loss increases with the increase in rotating speed and mass flow rate. Finally, four structures were compared, and an optimal structure with a separated outlet channel was identified as the best structure to eliminate this great pressure loss. Full article

The influence of supercritical CO₂ on the properties of petroleum has become the focus of academic and industrial attention internationally. CO₂ has been shown in laboratory studies and in field applications of shale oil to be an effective oil displacement agent. In this paper, the research progress of the interaction between CO₂ and crude oil is investigated from three perspectives: (i) the research methods of the interaction experiment between CO₂ and crude oil; (ii) the influence of CO₂ on oil property and the primary controlling factors; and (iii) the cause, influence, and harm of CO₂-induced asphaltene precipitation. Our current knowledge on this topic is as follows: (1) Physical simulation can investigate the effects of various variables on CO₂ displacement, which is in situ and intuitive. Numerical simulation can investigate the displacement principle at the microscopic molecular level and also scale up the results of physical simulation to the macroscopic scale of oilfield production to explore the long-term large-scale injection rules; (2) after entering the formation, CO₂ dissolves in crude oil, expands the volume of crude oil, reduces the viscosity, improves the oil–water mobility ratio, reduces the oil–water interfacial tension, and extracts light hydrocarbons to form a miscible displacement zone; (3) after CO₂ is injected into the formation and dissolves in crude oil, it occupies the surface space of asphaltenes and causes asphaltenes to precipitate. Under the combined influence of internal and external factors, the precipitation of asphaltenes has a significant impact on the physical properties of the reservoir. Clarifying the influencing factors of CO₂ on the property of crude oil has reference significance for understanding the reaction characteristics between supercritical CO₂ and formation fluids, providing a theoretical basis for CO₂ injection enhanced oil recovery technology, and has reference value for carbon storage research. Full article

The essential oil (EO) of Schinus areira exhibits a chemical composition dominated by monoterpene and sesquiterpene hydrocarbons, with α-phellandrene, limonene, α-pinene, and p-cymene as major constituents. This study aimed to evaluate the effects of S. areira EO on the biology and behavior of the Mediterranean fruit fly, Ceratitis capitata, particularly its attraction to the EO and the impact on its reproductive behavior and survival. Females were attracted at the initial choice and the time spent in the arm of the Y-tube olfactometer with the EO was longer, while males were attracted at the final choice, indicating the attractive potential of S. areira EO for both sexes of C. capitata. Within the context of the sterile insect technique (SIT), the better performance of released sterile males allows more copulations with wild females in competition with wild males, increasing the efficacy of the SIT. Exposure of tsl sterile males to the EO did not enhance their sexual competitiveness and increased latency to initiate copulation, indicating potential adverse effects. In addition, in oviposition assays, only a low concentration of the EO stimulated egg-laying on treated substrates, possibly due to the absence of deterrent compounds such as linalool. Finally, the LD50 of the EO was <25 µg/fly for both females and males, at 72 h post-treatment. These findings highlight the potential of EOs as biopesticides that influence the behaviors of C. capitata and emphasize the need for further studies to optimize their application in integrated pest management strategies, including the SIT. Full article

This article compares two new textile materials used to clean up spills of oil or two oil products (crude oil, diesel fuel, and base oil SN 150). The plain-woven cotton fabric is hydrophilic, with a typical porous structure. After coating with a layer of chitosan modified with benzaldehyde and cross-linked with glutaraldehyde (CB), its hydrophobicity increases, hence the sorption affinity to hydrophobic hydrocarbons. Including in situ synthesized zinc oxide particles in the hydrophobic chitosan layer (CBZ) changes its structure and increases the sorption capacity. The morphology of the layers was assessed using scanning electron microscopy (SEM) and by comparing the contact angles of the pollutants against the cotton fabric and the composite materials. EDX analysis and mapping for the Zn element show that zinc is homogeneously distributed on the fabric surface. The roughness enhancement and mesoporous structure under the influence of zinc oxide particles were established by the Brunauer Emmett Teller (BET) method and atomic force microscopy (AFM). The advantages of textile composites are their flexibility, stability, and ability to float on the water and wipe up oil spills. It was found that the materials can be successfully regenerated and used repeatedly, making them highly effective because the sorbed crude oil or petroleum products can be separated and utilized. Full article

It is well known that the host response to different human and animal coronaviruses infection is regulated by the aryl hydrocarbon receptor, a ligand-activated transcription factor. The present study investigates the expression of the aryl hydrocarbon receptor during bovine coronavirus infection, through in vitro and in silico investigations. The in vitro studies demonstrate that the aryl hydrocarbon receptor and as well as its targets, CYP1A1 and CYP1B1, were significantly activated by bovine coronavirus infection in bovine cells (MDBK). During infection, the pretreatment of cells with non-cytotoxic doses of CH223191, a selective inhibitor of the aryl hydrocarbon receptor, resulted in a significant reduction in virus yield and a downregulation in the viral spike protein expression. These findings occurred in the presence of the inhibition of aryl hydrocarbon receptor signaling. Our results reveal that the bovine coronavirus acts on viral replication, upregulating the aryl hydrocarbon receptor and its downstream target proteins, CYP1A1 and CYP1B1. In addition, following the in silico studies, the three-dimensional structural model of the bovine aryl hydrocarbon receptor in complex with the antagonist CH223191 indicates that the molecular mechanism, by which the PASB and TAD domains of the receptor interact with the inhibitor, is mainly driven by an extensive network of hydrophobic interactions, with a series of hydrogen bonds contributing to stabilizing the complex. Interestingly, bioinformatic analyses revealed that the PASB and TAD domains in the human and bovine aryl hydrocarbon receptor present high similarity at the primary sequence and three-dimensional structure levels. Taken together, these findings represent a fundamental step for the development of innovative drugs targeting AhR as a potential object for CoVs therapy. Full article

Coal is an important energy source for the development of modern society. The processing and utilization of coal have brought significant economic benefits for people, but at the same time, a large amount of coal-based solid waste is produced. Coal tar slag is one of the many types of solid waste. Coal tar slag contains a large number of PAHs (Polycyclic Aromatic Hydrocarbons) that are carcinogenic to humans and are therefore categorized as hazardous waste. There is a large historical stockpile of coal tar slag, and if not properly handled, it will cause great harm to people and the environment; therefore, the disposal of coal tar slags is a hot issue for scholars to study. In this paper, the toxic PAHs in coal tar slag were removed by subcritical extraction, and the extracts and raffinates were tested using infrared spectroscopy, GC-MS (gas chromatography–mass spectrometry), and PY-GC-MS (Pyrolysis Gas Chromatography–Mass Spectrometry). The results showed that after three subcritical extractions at 60 °C, there were obvious aromatic hydrocarbon absorption peaks in the extracts, and the intensity of aromatic hydrocarbons in the extracts was significantly reduced. In the first extract, mainly aliphatic hydrocarbons and aromatic hydrocarbons dominated; the relative content of aliphatic hydrocarbons was 28.68%, and the relative content of aromatic hydrocarbons was 56.56%. In the second extract, mainly aliphatic hydrocarbons and ethers dominated; the relative content of aliphatic hydrocarbons was 37.11%, and the relative content of ethers was 18.5%. In the third extract, mainly aliphatic hydrocarbons dominated, and the relative content of aliphatic hydrocarbons was 81.78%. Only one substance, benzaldehyde, was detected in the PY-GC-MS results of the third extract, and this substance is not included in the national hazardous waste list. After subcritical extraction, the coal tar residue is transformed from coal-based hazardous waste to coal-based solid waste that can be used directly, which is convenient for people to recycle coal tar residue in the future. Full article

In countries with a long petroleum extraction and processing history, such as Romania, extensive soil areas are often polluted with petroleum and its derivatives, posing significant environmental and human health risks. This study explores the diesel biodegradation potential of two native bacterial consortia isolated from hydrocarbon-polluted soils, focusing on their phenotypic and molecular characteristics, growth kinetics, alkane hydroxylase activity, hydrolase production, and biosurfactant synthesis capabilities. The bacterial consortia, CoP1 and CoP2, were successfully obtained using the standard successive enrichment culture method from two soil samples collected from a region affected by petroleum pollution. The CoP1 and CoP2 consortia demonstrated efficient diesel-degrading capabilities, achieving 50.81−84.32% degradation when cultured in a minimal medium containing 1–10% (v/v) diesel as the sole carbon and energy source. This biodegradation potential was corroborated by their significant alkane hydroxylase activity and the detection of multiple catabolic genes in their genomes. The CoP1 consortium contains at least four catabolic genes (alkB, alkM, todM, ndoM) as well as rhamnosyltransferase 1 genes (rhlAB), while the CoP2 consortium contains only two catabolic genes (ndoM, C23DO). The RND transporter gene (HAE1) was present in both consortia. Secondary metabolites, such as glycolipid-type biosurfactants, as well as extracellular hydrolases (protease, amylase, cellulase, and lipase), were produced by both consortia. The CoP1 and CoP2 consortia demonstrate exceptional efficiency in diesel degradation and biosurfactant production, making them well suited for the bioremediation of soils contaminated with petroleum and its derivatives. Full article

This parameter study examines the impact of two distinct adhesion layers, chromium (Cr) and titanium (Ti), on the performance of CuO/Cu₂O-based chemoresistive gas sensors by varying the layer thickness. The sensing material utilised on a Si-SiO₂ sensor chip with Pt electrodes is an ultrathin CuO/Cu₂O film fabricated through thermal deposition of Cu and subsequent oxidation. The sensors were evaluated by measuring the change in electrical resistance against a range of target gases, including carbon monoxide (CO), carbon dioxide (CO₂) and a mixture of hydrocarbons (HC_Mix), in order to assess any potential cross-sensitivity issues. As the reactions occur at the surface, the surface was characterised by scanning electron microscopy (SEM) and the composition by grazing incidence X-Ray diffraction (GIXRD) measurement to gain further insight into the influence of the adhesion layer on the sensing performance. Full article

The article presents a comprehensive analysis of long-term studies on hydrogen-hydrocarbon free gases (FGs) in the rocks of the Khibiny massif, systematically organized and generalized for the first time. Gasometric observations were predominantly conducted within underground mine workings, with occasional measurements taken during the drilling of exploration boreholes at the surface or in subsurface air within loose sediments. Methane is the primary component of these gases, followed in descending order by hydrogen, ethane, helium, other methane homologs, and alkenes. Nitrogen is also presumed to be present, although its proportions remain undefined. The carbon and hydrogen in FGs exhibit relatively heavy isotopic compositions, which progressively lighten from methane to ethane. The intensity of gas emissions is characterized by a gas flow rate from shot holes and boreholes, reaching up to 0.5 L/min but generally decreasing significantly within an hour of reservoir exposure. Gas-bearing areas, ranging in size from a few meters to tens of meters, are distributed irregularly and without discernible patterns. The FG content in rocks and ores varies from trace amounts to approximately 1 m³ of gas per cubic meter of undisturbed rock. These gases are primarily residual, preserved within microfractures and cavities following the isolation of fluid inclusions. Their distribution and composition may fluctuate due to the dynamic geomechanical conditions of the rock mass. The release of flammable and explosive FGs presents a significant hazard during ore deposit exploration and development, necessitating the implementation of rigorous safety measures for mining and drilling operations. Additionally, the environmental implications and potential applications of gas emissions warrant attention. Future comprehensive studies of the Khibiny gases using advanced methodologies and equipment are expected to address various scientific and practical challenges. Full article

Background/Objective: The aryl hydrocarbon receptor (AHR) is an important mediator of intestinal homeostasis. The AHR senses certain classes of phytochemicals, including many flavonoids and tryptophan metabolites generated in the intestinal tract. Several in vitro studies demonstrate the presence of AHR ligands in numerous plants commonly consumed by humans. However, it has not been established that these foods can activate the AHR in vivo. The aim of this study was to evaluate how phytochemicals in foods can lead to AHR activation in vivo through modulating CYP1A1 activity. Methods: Freeze-dried spinach, corn, red potatoes, kidney beans, parsley, onion, carrots, bell peppers, and broccoli were fed to C57BL6/J female mice at 15% w/w in a semi-purified diet to evaluate the AHR activation potential. In vitro CYP1A1 microsomal assays were utilized to establish specific phytochemicals as CYP1A1 substrates. Results: Broccoli, onion, and carrots increased expression of the AHR target gene Cyp1a1 in the duodenum. Broccoli consumption led to the formation of the potent AHR ligand indolo[3,2-b]carbazole (ICZ), which is also a CYP1A1 substrate. Relative to the other vegetables, parsley contained a high concentration of apiin, a diglycoside of the flavone apigenin. Mice were fed a diet with either 10% parsley, 10% broccoli, or both vegetables. Parsley consumption increased broccoli-mediated Cyp1a1 induction in the duodenum, liver, and lung. Apigenin is a CYP1A1 substrate that can attenuate ICZ metabolism in vitro and increase broccoli-mediated Cyp1a1 expression in the lung. Conclusions: These results suggest that phytochemical competition for intestinal AHR binding and CYP1A1 metabolism modulates systemic AHR activity. Full article