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The Ri-Qing-Wei Basin is a newly discovered Late Mesozoic rift basin on the eastern Shandong coast in recent years. Thick, continuous deposited source rocks are found in the Lingshan Island scientific drilling project. Therefore, it is necessary to evaluate the distribution and hydrocarbon generation potential of source rocks in this area. Organic geochemical experiments were carried out on samples from the core of LK-1 and outcrops in the Lingshan Island, the Laoshan area, and the Jimo Zhougezhuang area to evaluate the maturity, abundance, and type of organic matter in source rocks. The results show that the cumulative thickness of the source rocks in the study area is more than 500 m, and the TOC content is generally greater than 1.0%. The organic matter type is good (mainly type II1 and type II2 kerogen) and the Ro value is more than 2.0. The thermal evolution degree of the organic matter is high with natural gas predominantly generated. We carried out Rock-Eval, PY-GC and gold tube experiments on low-maturity samples of Laikong 2 and established a chemical kinetic model to quantitatively evaluate the study area in combination with sedimentary burial history and thermal history data. The results show that the total resources of the five sags in the study area are about 476 billion cubic meters, and the average resource intensity is about 82.2 million cubic meters/km2. Among them, the resource intensities of the Lingshan Island Sag and Laoshan Sag are 112.6 million cubic meters/km2 and 98.8 million cubic meters/km2, respectively. Studied sites are "small and fertile" and may be used as favorable exploration prospect areas. [ABSTRACT FROM AUTHOR]

Geochemical characteristics of sedimentary rocks play an important role in indicating depositional environments and tectonic backgrounds. In this article, the major and trace elements of the Daohugou Formation are measured, which shows that the quartz and silicate minerals are abundant; trace elements, except for Rb, are depleted than that of the upper crust; the rare earth elements (REE) curves incline to the right with Eu negative anomaly and slight Ce negative anomaly. The Daohugou Formation is continental deposits with freshwater and oxic conditions, and the climate changes from warm and humid to hot and dry. The source rock of the Daohugou Formation is granite which experienced an intermediate chemical weathering under wet and warm conditions, and the tectonic background of the Daohugou Formation is a passive continental margin. It is deduced that the provenance of the Daohugou Formation is Archean gneiss in the south of the Daohugou Basin. [ABSTRACT FROM AUTHOR]

Dawsonite commonly occurs in CO 2 -enriched strata and gas reservoirs, which is the product of CO 2 trapping or "mineral fixation". In this study, we focused on dawsonite and conducted series of experiments with three groups of variables: temperature (80/100/120/140 °C), pH (4/6/7/9), pCO 2 (0/4.3 Mpa) for comparison, aiming at understanding potential natural processes within CO 2 –H 2 O–dawsonite bearing sandstones systems. We conducted a series of studies on the alteration characteristics of dawsonite-bearing sandstones, evolutionary mode of fluid properties, alteration of dawsonite by fluid, and the mechanism of mineral precipitation and dissolution in closed systems. Based on Scanning Electron Microprobe (SEM) observation, energy spectrum analysis, X-ray diffraction analysis, and thermodynamic numerical simulation, we evaluated the influences of temperature, pH and pCO 2 on the stability of dawsonite preserved in sandstone, and further identified the favorable conditions for mineral trapping of CO 2. The hydrothermal experiments suggested that: for the temperature in the range of 80 °C–140 °C, the stability of dawsonite decreased with increasing temperature, and the fluid alteration influence on dawsonite mainly followed transformation path. When the pH is in range of 4–9, the stability of dawsonite decreased with the decreasing pH, and the alteration of dawsonite by fluid mainly followed decomposition path. pCO 2 decided the thermal stability of dawsonite, and when pCO 2 increased from 0 MPa to 4.3 MPa, the degree of dawsonite corrosion decreased and its stability increased. The results of hydrothermal experiment agree well with the thermodynamic numerical simulation, and indicate that the alkaline closed system with low temperature and high pCO 2 is ideal for "Carbon Capture and Storage", which can promote the formation and conservation of CO 2 "entrapment minerals", and benefit the long-term and stable geological CO 2 sequestration. • Establish the effects of temperature, pH, pCO 2 on the stability of dawsonite in sandstone. • Discuss the alteration paths of dawsonite by fluid. • Indicate the dissolution and precipitation mechanism of carbonates in various conditions. • Identify the ideal environment for the formation and conservation of CO 2 "entrapment minerals". [ABSTRACT FROM AUTHOR]

Abstract Shales in China mainly fall into three categories, namely marine, transitional and lacustrine shales. Various shales have different pore characteristics. We studied the formation, occurrence, pore types and morphological characteristics of micropores, mesopores and macropores in different types of shales through the approaches of gas adsorption and mercury injection. Our study found that the marine shale samples have larger specific surface area and pore volume, providing a good hosting space for adsorption gas and free gas. Furthermore, marine samples are dominated by ink-bottle pores, which are conducive to adsorption of shale gas. Continental and transitional pore types are mainly open pores, characterized by good pores' connectivity that is conducive to the migration of shale gas. The main factors controlling the pore characteristics of the three types of shales were analyzed by investigating specific surface area, pore volume, organic content, clay mineral content, maturity and burial depth. Our study demonstrated that specific surface area and pore volume development have a good correlation with organic matter in the three types of shales. Types of organic matter can affect the development of organic pores. The discrepancy in occurrence of organic matter leads to different correlations between the three types of shales and clay minerals. On the other hand, maturity impacts on pores of shales in two aspects: organic matter and clay mineral transformation. Meanwhile, compaction and dissolution of organic acid in hydrocarbon-generation process are proved to be especially important to pore structure transformation. Highlights • The shale in China includes three categories, namely marine, transitional and lacustrine shale. • Organic content, clay mineral content, maturity and burial depth controll the pore characteristics. • Compaction and organic acid dissolution are important to pore structure transformation. [ABSTRACT FROM AUTHOR]

Circulating tumour cells (CTCs) draw significant attention as a promising biomarker for cancer prognosis, status monitoring, and metastasis diagnosis. However, the concentration of CTCs in peripheral blood is usually extremely low, thereby requiring enrichment followed by isolation of CTCs prior to detection. An immunomagnetic separation is a promising tool for CTCs enrichment. In this study, a cost‐effective magnetic separation method, based on streptavidin–biotin complexation, was developed and the effects of magnetic beads' size in CTCs capture were compared. Magnetic nanobeads which were 25 nm in diameter lead to highest capture efficiency (82.2%) compared with 150 nm magnetic beads and 1 µm microbeads. Based on the streptavidin–biotin system, 25 nm magnetic nanobeads could capture model CTCs over 80% efficiency even at concentrations as low as ∼25 cells/mL that may represent the actual level of CTCs in peripheral blood of cancer patients. Furthermore, the isolated cells remained robust and healthy showing insignificant changes in morphology and behaviour when cultured for 24 h immediately after capture and isolation. The magnetic nanobeads based on streptavidin–biotin complexation showed promise for the easy and efficient capture and isolation of healthy CTCs for further diagnosis and analysis. [ABSTRACT FROM AUTHOR]

The Shengli Oilfield is discussed to investigate CO2 trapping mechanisms involved in geothermal oil reservoir systems. Diagenetic fluid evolution of the dawsonite‐bearing sandstones from the Dongying Sag, Bohai Bay Basin, China, was studied to understand the CO2 migration and accumulation and the formation of dawsonite, as a possible mechanism for mineral trapping of CO2 in geothermal fields. Information about the petrology, dawsonite‐forming fluid, authigenic mineral associations, and diagenetic fluid evolution mode was analysed using techniques including thin‐section identification, scanning electron microscope observation, X‐ray diffraction analysis, X‐ray fluorescence spectrum analysis, hydrochemistry, and stable isotope analyses. The paragenetic sequence, from early to late, is early calcite (A)–compaction–dissolution–quartz overgrowth–late calcite (B1)–ferrocalcite (A)–dawsonite–late calcite (B2)–ferrocalcite (B)–ankerite–siderite or pyrite. The current in situ formation water type of the dawsonite‐bearing sandstone strata is NaHCO3, with the typical characteristics of weak alkaline, high mineralization, and high Na+ + K+ and HCO3− content. The formation fluid from which the dawsonite forms is mainly sealed underground brine, which has been affected by atmospheric precipitation and magmatic activity, and is thus mixed with surface meteoric water and subsurface hydrothermal fluid. The fluid evolution process sequence is alkaline fluid environment prior to CO2 influx, an early micritic or sparry calcite (A) association; acidic fluid environment after CO2 influx, a quartz overgrowth and kaolinite association; alkalescent fluid environment, an association of late calcite (B1), ferrocalcite (A), and illite; alkaline fluid environment, a dawsonite and late calcite (B2) association; and weak‐alkaline fluid environment, an association of ferrocalcite (B), ankerite, siderite, and pyrite. [ABSTRACT FROM AUTHOR]

Infectious diseases caused by Listeria monocytogenes pose a great threat to public health worldwide. Therefore, a rapid and efficient method for L. monocytogenes detection is needed. In this study, a biotin-exposure-based immunomagnetic separation (IMS) method was developed. That is, biotinylated antibody was first targeted to L. monocytogenes . Then, streptavidin-functionalized magnetic nanoparticles were added and anchored onto L. monocytogenes cells indirectly through the strong noncovalent interaction between streptavidin and biotin. Biotin-exposure-based IMS exhibited an excellent capability to enrich L. monocytogenes . Specifically, more than 90% of L. monocytogenes was captured when the bacterial concentration was lower than 10 4  colony-forming units (CFU)/mL. Importantly, the antibody dosage was reduced by 10 times of that in our previous study, which used antibody direct-conjugated magnetic nanoparticles. Propidium monoazide (PMA) treatment prior to PCR amplification could eliminate the false-positive results from dead bacteria and detected viable L. monocytogenes sensitively and specifically. For viable L. monocytogenes detection, enriched L. monocytogenes was treated with PMA prior to asymmetric PCR amplification. The detection limits of the combined IMS with nucleic acid lateral flow (NALF) biosensor for viable L. monocytogenes detection were 3.5 × 10 3  CFU/mL in phosphate buffer solution and 3.5 × 10 4  CFU/g in lettuce samples. The whole assay process of recognizing viable L. monocytogenes was completed within 6 h. The proposed biotin-exposure-mediated IMS combined with a disposable NALF biosensor platform posed no health risk to the end user, and possessed potential applications in the rapid screening and identification of foodborne pathogens. [ABSTRACT FROM AUTHOR]

Dawsonite has the potential to serve as a significant mineral for carbon sequestration in geological storage, and its stability in the reservoir is determined by intricate fluid-rock interactions. Thus, it is crucial to elucidate the mechanism that influences the stability of dawsonite. In this study, a natural dawsonite-bearing sandstone in Dongying Sag was utilized for CO 2 –H 2 O-Rock interaction experiments and TOUGHREACT numerical simulations at varying CO 2 pressures. Additionally, the CO 2 fugacity value acting on the sandstone in the reactor experiment was corrected using thermodynamic analysis. By systematically analyzing the dissolution response and elemental composition evolution of dawsonite through techniques such as scanning electron microscopy observation and energy spectrum analysis, X-ray diffraction analysis, hydrochemical analysis, and dawsonite stability indicator parameters, the influence mode on the stability of dawsonite was clarified. The atomic ratio of dawsonite in each experimental group (between Al:O = 1:3 and Al:O = 1:2) suggested that gibbsite and boehmite were formed after the dissolution of dawsonite under high CO 2 pressure. When pCO 2 ≤7.3 MPa or pCO 2 ＞8.3 MPa, increasing the CO 2 pressure could enhance the thermal stability of dawsonite and inhibit its decomposition. However, when pCO 2 was between 7.3 MPa and 8.3 MPa, the reaction equilibrium was disrupted, and a considerable amount of dawsonite was dissolved and transformed into new minerals. Both physical experimentation and numerical simulation indicated that dawsonite achieved a stable state at pCO 2 = 7.3 MPa and 120 °C. • The transformation effect of dawsonite under different CO 2 partial pressures and temperature conditions is summarized. • With the increase of CO 2 partial pressure, the stability of dawsonite tends to increase. • The evolution mode of dawsonite under different CO 2 pressures is summarized. [ABSTRACT FROM AUTHOR]

The detection of circulating tumor cells (CTCs) offers a noninvasive method for early-stage cancer diagnosis. Although this is a challenging process, the detection and enumeration of CTCs are essential for assessing cancer progression. In this study, we demonstrated an inexpensive and simple method that used folic acid, FA, as targeting probe to replace antibodies for the enrichment and isolation of ovarian cancer CTCs. Bovine serum albumin (BSA) was decorated on magnetic nanoparticles (MNP) to form BSA-MNP, while FA was conjugated on the BSA-MNP surface through a PEG 2K -linker. The FA-BSA-MNP complex showed efficient capture of ovarian cancer CTCs as low as 20 cells/mL. Moreover, this FA-BSA-MNP complex showed minimal nonspecific adsorption between the modified magnetic nanoprobes and ovarian cancer cells, resulting in high specific enrichment. More importantly, the MNP-BSA-FA complex was nontoxic to ovarian cancer cells. The isolated cancer cells remained highly viable, were readily grown in vitro without significant death rate with a viability of 92.7%, and without microscopically visible contamination. These results suggested that the FA-BSA-MNP complex could successfully be used for the capture of ovarian cancer CTCs from whole blood. Moreover, when combined with immunocytochemical staining method, the FA-BSA-MNP captured CTCs could be differentiated from the blood cells. [ABSTRACT FROM AUTHOR]

In this study, we developed a PAMAM dendrimer-mediated biotin amplified magnetic separation method that was coupled with flow cytometry (FCM) for viable L. monocytogenes detection. PAMAM dendrimer-mediated biotin amplified magnetic separation strategy isolated more than 89.15% ± 1.75%  L. monocytogenes both in PBS solutions and in spiked lettuce samples at bacterial concentration below 10 4 CFU/mL. Propidium monoazide (PMA) treatment prior to PCR amplification eliminated the false-positive results from dead bacteria and detected viable L. monocytogenes sensitively and specifically. In this assay, a pair of specific primers was synthesized for the hly gene of L. monocytogenes that was modified with biotin and FAM (FITC) respectively. After PCR amplification, biotin and FAM (FITC) labeled amplicons were immobilized on the streptavidin coated magnetic microbeads, and the mean fluorescence intensity (MFI) of the microbeads was measured with flow cytometer. Combined PAMAM dendrimer-mediated biotin amplified magnetic separation with FCM assay for viable L. monocytogenes detection, and gave a limit of detection (LOD) as low as 3.5 × 10 1 CFU/mL in PBS and 3.5 × 10 2 CFU/g in spiked lettuce samples. Moreover, the method developed exhibited excellent specificity. Therefore, PAMAM dendrimer-mediated biotin amplified magnetic separation method coupled with FCM assay is a highly promising approach for L. monocytogenes detection. [ABSTRACT FROM AUTHOR]

Emetic Bacillus cereus is a common foodborne pathogen that can cause vomiting after ingesting the contaminated food. Detection of emetic B. cereus plays an important role in food industry. In this study, a flow cytometric bead assay based on hybridization chain reaction (HCR) were developed to detect emetic B. cereus . Forward primer labeled magnetic beads (MBs) could capture single-strand DNA (ssDNA), which were generated through the asymmetric polymerase chain reaction from the partial cereulide-encoded gene of emetic B. cereus . Then the ssDNA initiated HCR to self-assemble with two fluorescent hairpin probes. Flow cytometry was then performed to monitor the HCR products of MBs. Under optimal experimental conditions, the limit of detection (LOD) for emetic B. cereus was 7.6 × 10 0 CFU/mL with a liner range from 7.6 × 10 0 CFU/mL to 7.6 × 10 6 CFU/mL in pure culture. The proposed strategy can be used in spiked milk with LOD of 9.2 × 10 2 CFU/mL without enrichment. The high specificity of the assay was verified using closely related strains, such as B. subtilis , non-emetic B. cereus . The proposed strategy offers a great promise for simple, low-cost, sensitive, and specific pathogen diagnosis in a real food matrix. [ABSTRACT FROM AUTHOR]

Bacillus cereus is a causative agent of an emetic food-borne disease. In this study, visual detection of viable emetic B. cereus was developed using a propidium monoazide (PMA)-asymmetric polymerase chain reaction (asPCR) and unmodified gold nanoparticles (AuNPs). To detect only the viable emetic B. cereus , PMA treatment was selected before DNA extraction to eliminate the false-positive results from dead bacteria. In the presence of viable target bacteria, the long genomic DNA fragments from the cereulide synthetase gene ( cesB ) were produced by asPCR, which could be effectively absorbed onto naked AuNPs via coordination between Au and the nitrogen atoms of the exposed bases. After adding NaCl solution, visual detection with the naked-eye or with UV–vis spectrophotometer was possible within a few minutes. Under the optimum conditions, the limit of detection (LOD) for viable emetic B. cereus reached as low as 9.2 × 10 1 CFU/mL in 0.01 M phosphate-buffered saline and 3.4 × 10 2 CFU/mL in milk, which was adequate to meet the maximum limit imposed by the Commission Regulation (EC) No 2073/2005 (500 CFU/mL). The proposed method also exhibited excellent discrimination against 10 common pathogenic bacteria in milk. The PMA-asPCR-AuNPs colorimetric assay offers a promising application in the detection of low concentrations of food-borne pathogens. [ABSTRACT FROM AUTHOR]

Dawsonite occurs in sandstones of the fourth member of the Shahejie Formation, Dongying Sag, Bohai Bay Basin, northeastern China. The paragenesis sequence, formation temperatures, carbon dioxide (CO 2 ) and aqueous medium origin of dawsonite from the Binnan Area were studied to understand the formation of dawsonite, as a possible mechanism for mineral trapping of CO 2 in carbon capture and storage (CCS) programs. The petrological and geochemical characteristics of the dawsonite-bearing sandstones were identified using polarizing microscope examination, scanning electron microscope, X-ray fluorescence, X-Ray diffraction and stable isotopic analyses. The paragenesis sequence of the authigenic minerals are mainly quartz overgrowth – early-stage calcite (A) – ferrocalcite– dawsonite – late-stage calcite (B) – ankerite – siderite. The carbon and oxygen isotope compositions of dawsonite reveal that δ 13 C values of dawsonite range from −2.27‰ to +3.50‰, indicating inorganic CO 2 . The calculated δ 13 C values of CO 2 gas in isotopic equilibrium with dawsonite range from −7.2‰ to −1.6‰, suggesting that CO 2 originated mainly from degassing of mantle-derived magmas and partly from thermal decomposition of carbonate rocks, as supported by regional magmatic activities, rifting, and observation of carbonate during drilling in well Bin76. The δ 18 O values of dawsonite vary from +17.2‰ to +19.8‰, and the calculated δ 18 O values of H 2 O in isotopic equilibrium with dawsonite range from −2.1‰ to +0.4‰. The mixed aqueous medium was mainly connate water, influenced by magmatic activities and meteoric water influx during the formation of dawsonite. According to oxygen isotope data, the formation temperatures of dawsonite in the Binnan Area range from 77 °C to 95 °C, which are consistent with the estimated paleo-temperatures (79 °C to 85 °C), indicating that the dawsonite formed at the late stage of the diagenetic phase. [ABSTRACT FROM AUTHOR]

In this study, vancomycin (Van) functionalized PEGylated-magnetic nanoparticles (Van-PMs) combined with polymerase chain reaction (PCR) showed great potential for highly efficient detection of L. monocytogenes at low infectious dose. Herein, Van-PMs played as universal molecular probes for targeting bacterial cells, while PEG was used to help Van close to D-alanyl- d -alanine (D-Ala- d -Ala) moieties on surface of L. monocytogenes . Under optimum conditions, the developed Van-PMs complexes exhibited extremely high capture efficiency (CE) in a 10 mL bacterium suspension with the value was higher than 90% and 83% in the phosphate-buffered saline (PBS) solution and lettuce samples, respectively. Meanwhile, Gram-negative bacteria slightly influenced CE even under concentrations as high as 10 6 CFU/mL. The assay of Van-PMs-PCR was applied to detect L. monocytogenes with detection limits of 30 CFU/mL and 30 CFU/g in PBS solution and lettuce samples, respectively. The whole experiment was completed within 4 h. This assay demonstrated the potential of this modified method in practical application involving the detection of L. monocytogenes or other Gram-positive pathogenic bacteria. [ABSTRACT FROM AUTHOR]

Salmonella is one of the most common pathogens that cause foodborne diseases in humans, resulting in high medical and economical costs worldwide. The aim of this study was to develop a rapid and accurate approach for simultaneous detection of viable Salmonella spp. in raw meat, including Salmonella enterica serovars Paratyphi B, S. Typhimurium, and S. Enteritidis. To reduce detection time and improve sensitivity, immunomagnetic separation (IMS) was used as a pre-concentration and separation method. In addition, false positive and false negative results were removed by combining propidium monoazide (PMA) treatment with internal amplification control. Results showed that the detection limit of IMS-PMA combined with sextuplex polymerase chain reaction (PCR) assay reached as low as 10 1 CFU/mL in pure culture and 10 2 CFU/g in spiked raw meat (ground pork and ground beef), and the total assay time took less than 6 h. Thus, the novel IMS-PMA-mPCR assay developed in this study holds promise for routine screening of viable Salmonella serovars in meat and other samples. [ABSTRACT FROM AUTHOR]

The article presents a study which investigates the pores characteristics and controlling factors of different types of shale in China. Approaches of high pressure Hg injection and cryogenic adsorption were used to reveal the storage mechanism of shale gas and evaluate the shale reservoir capacity. Results of the analysis reveal the difference in pore diameter distribution and formation mechanisms of the shale.

Protein phosphorylation, one of the main protein post-translational modifications, is required for regulating various life activities. Kinases and phosphatases that regulate protein phosphorylation in humans have been targeted to treat various diseases, particularly cancer. High-throughput experimental methods to discover protein phosphosites are laborious and time-consuming. The burgeoning databases and predictors provide essential infrastructure to the research community. To date, >60 publicly available phosphorylation databases and predictors each have been developed. In this review, we have comprehensively summarized the status and applicability of major online phosphorylation databases and predictors, thereby helping researchers rapidly select tools that are most suitable for their projects. Moreover, the organizational strategies and limitations of these databases and predictors have been highlighted, which may facilitate the development of better protein phosphorylation predictors in silico. [ABSTRACT FROM AUTHOR]

As a new type of liquid biopsy, circulating tumor cell (CTC) detection and analysis offers the possibility to monitor metastatic development, cancer recurrence, and therapeutic efficacy in real time. However, the inherent rarity and heterogeneity of CTCs pose great challenges for CTC detection and analysis. Effective CTC capture and detection are therefore of great importance in cancer diagnosis and prognosis. Since virtually all biological materials are diamagnetic or only weak magnetic, magnetic particle-based magnetic capture and isolation methods are promising as CTC catchers. In this review, we focus attention on the progress of technologies utilizing magnetic particles to assist CTCs capture. We summarized the influence of the physicochemical properties of magnetic particles on CTC enrichment, and some general strategies for enhancing CTC capture based on magnetic particles. In addition, we also reviewed some of the application progress of magnetic nanoparticles in CTC capture and analysis. • We reviewed the technologies utilizing magnetic particles to assist CTCs capture. • Illustrated the effects of MPs physicochemical properties on CTCs capture. • Summarized the CTC capture model and common strategies to enhance CTC capture. • Presented the application of MPs in vivo for CTC detection and elimination. [ABSTRACT FROM AUTHOR]

Joint seismic and controlled‐source electromagnetic surveys can reduce uncertainty and improve hydrocarbon quantification. However, the successful interpretation of joint seismic and controlled‐source electromagnetic survey data requires a valid rock physics model to link the elastic and electrical rock properties. A cross‐property differential effective medium is recently proposed with pores embedded in the mineral matrix. We have presented a technique to test the applicability of the cross‐property differential effective medium model to the joint elastic‐electrical properties of reservoir sandstones. The method is based on the common employment of measured sample porosity and inverted equivalent pore aspect ratio from cementation exponent for the modelling. Application of the modelling approach to a laboratory joint elastic‐electrical dataset shows that there is a systematic discrepancy in the modelled and measured joint elastic–electrical properties. It is also found that an equivalent pore aspect ratio is existing to reasonably predict the trend of the joint elastic–electrical data; however, the porosity used in the modelling is far from their measured values. Conversely, if the measured sample porosity is employed, the mentioned equivalent pore aspect ratio fails to fit either of the measured elastic and electrical rock properties. The results indicate the incapability of the cross‐property differential effective medium model for the joint elastic–electrical modelling of reservoir rocks and suggest the requirement of a new model to link the elastic and electrical properties. [ABSTRACT FROM AUTHOR]

The downhole working conditions of oil fields are harsh and complex, and the working performance of tools is affected by erosion and wear after being washed by sand laden mud. In order to improve the service life of downhole tools and optimize the material with excellent anti-erosion properties, the anti-erosion properties of three common metal materials are studied in this paper. By analogy with the difficulty of abrasive water jet cutting materials, the erosion wear ability of sand laden mud on the shell of downhole tools is equivalent evaluated, and the time dimension is shortened, which is prone to analyze the erosion wear resistance of different materials. Then, a numerical model of abrasive particles impact on the material surface, based on the finite element method–smoothed particle hydrodynamics coupled method, is established, the deformation and material removal amount of different materials under the same erosion condition are compared and analyzed, and the reasons for the difference in anti-erosion properties of different materials are quantitatively analyzed from the microscopic point of view. The results showed that under the same erosion conditions, the material removal amount 40CrNi2Mo < 45Steel < Ti6Al4V, and the anti-erosion properties decreases sequentially, which is not affected by erosion velocity V (jet pressure P) and waterjet sand ratio ζ. Among them, the material deformation and removal of 40CrNi2Mo and 45Steel are similar, and the anti-erosion properties of the two are approximately the same. [ABSTRACT FROM AUTHOR]

Hydrogen holds promise as a clean energy carrier, but its industrial utilization is currently constrained by the challenges of green production and efficient cross-regional delivery. To this end, a novel integrated hydrogen energy system considering the solar-driven biomass gasification and liquid organic hydrogen storage was developed in this work. In the newly developed system, the collected high-temperature solar thermal energy is used to drive biomass gasification, and the produced syngas is then directed into methanol synthesis reaction. The unreacted syngas from methanol synthesis and the released waste heat are utilized by a Brayton-Rankine combined cycle for power generation. At the terminal side of hydrogen consumption, the mid/low-temperature solar thermochemical technology is adopted, and the produced methanol as the hydrogen carrier is thus decomposed to release the required hydrogen. The thermodynamic and economic evaluation models are developed to comprehensively investigate the system performances, and a designed annual biomass gasification processing capacity scenario of 153.0 ktons in China is implemented for the case study. The results indicate that the on-design energy and exergy efficiencies of the system reach 52.9% and 46.7%, respectively. Based on the elemental migration analysis, 51.3% of hydrogen element will be exported as the gaseous hydrogen, and only 21.4% of carbon is finally dissipated into the environment. According to the off-design evaluation during a typical year, the annual production rates of the hydrogen and electricity reach 11.2 ktons and 20.3 GWh, and the solar thermochemistry modules occupy the main initial investment. The research findings provide a promising approach for the efficient utilization of abundant solar energy and biomass energy resources. • An integrated H 2 system based on solar thermochemistry and methanol storage is proposed. • The system thermodynamic and the elements migration characteristic are investigated. • The cross-regional off-design dynamic operation performance of the system is analyzed. • The preliminary economic characteristics of integrated hydrogen system is evaluated. [ABSTRACT FROM AUTHOR]

Fine‐grained sedimentary rocks often contain hydrocarbon and mineral resources. Compared with coarse‐grained sedimentary rocks, fine‐grained sedimentary rocks are less studied. To elucidate the lithofacies and pore structure of lacustrine fine‐grained rocks, the 340.6 m continuous core of Cretaceous Qing‐1 Member from five wells in the southern central depression of the Songliao Basin was analyzed using X‐ray diffraction, Rock‐Eval pyrolysis, low‐temperature nitrogen adsorption, high‐pressure mercury injection, argon ion polishing‐field emission scanning electron microscopy, and laser scanning confocal microscopy. Based on mineral compositions, organic matter abundance and sedimentary structure, lacustrine fine‐grained rocks in the study area were divided into ten lithofacies, with their spatial distributions mainly influenced by tectonic cycle, climate cycle and provenance. Furthermore, pore structure characteristics of different lithofacies are summarized. (1) The siliceous mudstone lithofacies with low TOC content and the laminated/layered clay‐bearing siliceous mudstone lithofacies with medium TOC content have the highest proportion of first‐class pores (diameter > 100 nm), making it the most favourable lithofacies for the accumulation of shale oil and shale gas. (2) The massive clay‐bearing siliceous mudstone lithofacies with low TOC content has the highest proportion of second‐class pores (diameter ranges from 10 to 100 nm), making it a favourable lithofacies for the enrichment of shale gas. (3) The massive clay‐bearing siliceous mudstone lithofacies with high TOC content has the highest proportion of third‐class pores (diameter < 10 nm), making it intermediate in gas storage and flow. Laser confocal oil analysis shows that the heavy component of oil is mainly distributed in the clay lamina, while the light part with higher mobility is mainly concentrated in the silty lamina. [ABSTRACT FROM AUTHOR]

Electrical surveys are among the most important geophysical applications to understand the subsurface Earth, where anisotropic rock matrix is frequently encountered. Knowledge of the electrical properties of such rocks and their relationships with information of geological features included in the anisotropic rocks is crucial for the interpretation of electrical survey data. For this purpose, we first derive rigorous theoretical models for the electrical anisotropy of transversely isotropic (TI) rocks with spheroidal inclusions. The models assume the anisotropic background behaves isotropically in the direction whey the electrical field is applied parallel to the TI axes, and account for both aligned and randomly distributed inclusions and reduce to classical electrical models in the case of isotropic background. We then study systematically, through the obtained new models, the combined effects of geometry, concentration and alignment of both conductive and insulating spheroidal inclusions on the electrical anisotropy of TI rocks. We show that for aligned inclusions, the impact of inclusion volume fraction and aspect ratio is most significant in the direction when the electrical conductivity is measured along and perpendicular to the inclusions for conductive and insulating inclusions, respectively. For randomly distributed inclusions, both horizontal and vertical conductivity increases with decreasing aspect ratio of conductive inclusions and decreases with reducing aspect ratio of insulating inclusions. Most importantly, it is shown that the effects of randomly distributed conductive and insulating inclusions on the electrical anisotropy are similar although the rocks with insulating inclusions exhibit greater electrical anisotropy. The results provide new insights into the roles of spheroidal inclusions on the electrical anisotropy of TI rocks and pave a way for the successful interpretation of electrical survey data acquired in anisotropic rocks. [ABSTRACT FROM AUTHOR]

Abstract The feldspar group is one of the most common types of minerals in the earth's crust. Feldspar alteration (including the whole processes of feldspar dissolution, transfer of released solutes, and secondary mineral precipitation) is ubiquitous and important in fields including resources and environmental sciences. This paper provides a critical review of feldspar alteration and its geological significance in shallow aquifers to deep hydrocarbon reservoirs, as assessed from peer-reviewed paper in the literature. A variety of mechanisms such as the surface reaction-controlled dissolution mechanism, the preferential leaching-diffusion controlled mechanism, the diffusion-precipitation controlled dissolution mechanism and the interfacial dissolution-reprecipitation mechanism have been proposed to be responsible for the dissolution of feldspars. Feldspar dissolution rates can be affected by the crystal structure, Al/Si ordering, temperature, pH, surface area, organic acids, chemical affinity, and precipitation of secondary minerals. Five main dissolution rate laws have been used to describe feldspar dissolution rates, including the linear transition state theory (L-TST) rate law, non-linear TST rate law, parallel rate law, stepwave model rate law, and partial equilibrium law. The rate inconsistency between laboratory experiments and field observations is interpreted with hypotheses that include the armoring effects of the coating secondary minerals on feldspar surfaces, the possible effects of leached layers, the approach to saturation with respect to feldspars, the inhibition by absorbed Al3+ on the feldspar surface, and the inhibition by simultaneous slow clay precipitation rates. The inorganic-original (meteoric water and deep hot water) and organic-original (kerogen and hydrocarbon degradation) hydrogen ion (H+) in a fluid can probably act as a significant catalyzer of fast dissolution of feldspars in shallow aquifers and deep hydrocarbon reservoirs. Various mineral assemblages including extensively leached feldspars with a wide range of associated amounts of clay minerals and quartz cements can be identified in subsurface reservoirs under different geological conditions. Feldspar dissolution can generate enhanced secondary porosities and rock permeability in open geochemical systems at shallow depth or at a moderate-deep depth where faults develop widely. While in closed geochemical systems at moderate-deep depth, feldspar dissolution is likely to generate redistributional secondary porosities and to decrease rock permeability. Authigenic clay minerals formed following feldspar dissolution alter rock wettability and affect the charging and entrapment of hydrocarbons in reservoir. Feldspar alteration may promote hydrocarbon degradation by promoting bioactivity or by consuming low molecular weight organic acids and CO 2 produced via oil degradation. Further work should be conducted to study hydrocarbon-water-feldspar interactions in deeply buried hydrocarbon reservoirs. Feldspar alteration may promote CO 2 sequestration by consumption of H+, generation of HCO 3 −, and pH buffering of formation water. K-feldspar alteration may also promote illitization in interbedded mudstones by supplying K+. [ABSTRACT FROM AUTHOR]

Abundant gas and condensate resources are present in the Kuqa foreland basin in the northern Tarim Basin, NW China. Most of the hydrocarbons so far discovered are located in foldbelts in the north and centre of the foreland basin, and the Southern Slope region has therefore been less studied. This paper focusses on the Yangtake area in the west of the Southern Slope. Basin modelling was integrated with fluid inclusion analyses to investigate the oil and gas charge history of the area. ID modelling at two widely spaced wells (DB‐1 and YN‐2) assessed the burial, thermal and hydrocarbon generation histories of Jurassic source rocks in the foreland basin. Results show that the source rocks began to generate hydrocarbons (Ro >0.5%) during the Miocene. In both wells, the source rocks became mature to highly mature between 12 and 1.8 Ma, and most oil and gas was generated at 5.3–1.8 Ma with peak generation at about 3 Ma. Two types of petroleum fluid inclusions were observed in Cretaceous and lower Paleocene sandstone reservoir rocks at wells YTK‐5 and YTK‐1 in the Yangtake area. The inclusions in general occur along healed microfractures in quartz grains, and have either yellowish or blueish fluorescence colours. Aqueous inclusions coexisting with both types of oil inclusions in Cretaceous sandstones in well YTK‐5 had homogenization temperatures of 96–128 °C and 115–135 °C, respectively. The integrated results of this study suggest that oil generated by the Middle Jurassic Qiakemake Formation source rocks initially charged sandstone reservoirs in the Yangtake area at about 4 Ma, forming the yellowish‐fluorescing oil inclusions. Gas, which was mainly sourced from Lower Jurassic Yangxia and Middle Jurassic Kezilenuer coaly and mudstone source rocks, initially migrated into the same reservoirs in the Yangtake area at about 3.5 Ma and interacted with the early‐formed oils forming blueish‐fluorescing oil inclusions. The migration of gas also resulted in formation of the condensate accumulations which are present at the YTK‐1 and YTK‐2 fields in the Yangtake area. [ABSTRACT FROM AUTHOR]

The article focuses on a study exploring the characteristics of the hydrocarbon accumulation as well as the tight sandstone reservoir in Daqing placanticline. It provides details about the study of the tight oil geology as well as the implementation of thin section observation, casting image, and scanning electron microscopy (SEM) analysis.

The Permian coaly source rocks of coal and carbonaceous mudstone contained more hydrogen-rich vitrinite and liptinite, and formed in the weak oxidation–reduction conditions. Coaly shale was characterized by a most hydrogen-poor vitrinite and deposited in the weak to the strong reduction environment. A comprehensively accumulation model of Permian coaly source rock was established. [Display omitted] • Differences on organic geochemical characteristics on coaly source rocks were analysed. • Different macerals contained in coaly source rock were discriminated. • Salinity and redox conditions of bottom water in the Permian coaly source rocks were outlined. • Depositional model of Permian coaly source rocks was established. The Carboniferous-Permian was an important period for the formation of coal mines and coaly source rocks across the world. Controlled by the paleoclimate, Cathaysia flora, and transitional sedimentary environment of the delta, the Early Permian Shanxi Formation in the Huanghua Depression formed several layers of coal and coaly source rocks that can be explored in the whole depression. However, the development regularity and distribution prediction of high-quality coaly source rocks are still not well understood. The coaly source rocks of the Shanxi Formation in the Huanghua Depression were taken as the research object. With the determination and analysis of organic carbon content, rock pyrolysis, and vitrinite reflectance, we found that the organic matter abundance (i.e., TOC which changed from 20.3 % to 80.0 %), hydrocarbon generation potential (i.e., S 1 + S 2 which varied from 7.82 mg/g to 208.81 mg/g), and kerogen types (mainly type II 2) of the coal were better than carbonaceous mudstone and coaly shale. Maceral component identification indicated that coal and carbonaceous mudstone had more liptinite (i.e. cutinite and sporinite)and hydrogen-rich vitrinite, while coaly shale was mainly composed of hydrogen-poor vitrinite and a small amount of liptinite. The analysis of the ratios of major and trace elements, normal alkanes, and isoparaffin suggested that the paleo-water salinity of coal and carbonaceous mudstone deposition was more than that of part coaly shale. Revealed by the weak reduction of their depositional environment, the development of high-quality coal and carbonaceous mudstone was mostly controlled by the input of oil- and gas-prone organic matter. The formation of high-quality coaly shale was chiefly dominated by a strong reduction environment with an insignificant amount of organic matter input. The formation model of high-quality coaly source rocks was established. This model can be used to predict the distribution of coal mines and coaly source rocks in the Huanghua Depression and Bohai Bay Basin. [ABSTRACT FROM AUTHOR]

Most of the domestic oil fields are in the middle or late stage of exploration and development, and there are fewer and fewer oil fields that can be easily discovered. Proved reserves are dominated by concealed reservoirs, but concealed reservoirs are difficult to find. The prediction for favorable reservoir is a key in the process of exploration and development, but the traditional prediction methods of favorable reservoir rely on analysis of geological prospectors according to commonly used seismic attributes, which leads to low exploration efficiency. To improve effectiveness of the prediction for favorable reservoir, this paper introduces a multi-classification Twin Support Vector Machine (MTWSVM) method suitable for the case of insufficient reservoir label samples caused by fewer drilling data, which is used to identify favorable reservoirs. Since each sub-classifier of existing MTWSVM uses the same penalty parameters and kernel parameters, ignoring the differences between different classes, it cannot play the best role of each sub-classifier. We propose a multi-classification Twin Support Vector Machine based on hybrid parameters (HP-MTWSVM). This algorithm selects appropriate parameters for different sub-classifiers, maintaining the diversity of classifiers. Twin Support Vector Machine (TWSVM) is facing the problem that its parameters are difficult to be appointed. Additionally, HP-MTWSVM algorithm introduces a large number of parameters. This paper further proposes a hybrid parameter multi-classification Twin Support Vector Machine based on Grey Wolf Optimizer (GWO-HP-MTWSVM). This method uses GWO to optimize the parameters of HP-MTWSVM. Experiments show that the prediction accuracy of GWO-HP-MTWSVM is more than 64%, better than that of manual prediction in complex concealed reservoirs. The model can help geological exploration personnel quickly delineate favorable areas, provide basis for accurately drilling wells and avoid waste of resources caused by empty reservoirs. • Machine learning method can improve the accuracy of favorable reservoir prediction. • The construction strategy and parameter selection of multi-classifier will affect the performance of classification model. • Improving construction strategy and optimizing model parameters can improve prediction performance. • A novel prediction method based on Grey Wolf optimization and twin support vector machine is developed. [ABSTRACT FROM AUTHOR]

• Pyrolysis experiments of palm oil were performed by TG-FTIR and Py-GC/MS. • The maximum heating rate of pyrolyzer was set to 10,000 °C s−1. • The pyrolysis reaction of palm oil follows 1.5 order reaction model. • The high heating rate can inhibit the formation of undesired products. In this work, the palm oil was selected as the model compound of waste cooking oil and the pyrolysis experiments were performed first by TG-FTIR and then via Py-GC/MS. TG-FTIR analysis showed that the temperature range of palm oil pyrolysis was 385.2 °C–488.4 °C and the volatile products were mainly CO, CO 2 and a large number of light hydrocarbon. According to kinetic analysis, palm oil pyrolysis followed the 1.5 order reaction model. The apparent activation energy and pre-exponential factor calculated by Coats-Redfern method were 275.257 KJ mol−1 and 4.252 × 1020 s−1. The fast pyrolysis experiments were performed at different final temperatures (500 °C, 550 °C, 600 °C, and 650 °C) and different heating rates (0.2 °C ms−1, 1 °C ms−1, 5 °C ms−1 and 10 °C ms−1). The GC/MS analysis indicated that the pyrolysis products mainly included saturated hydrocarbons, unsaturated hydrocarbons, aromatic hydrocarbons, carbonyl compounds and other oxygenates. As the final temperatures increased, the relative content of carbonyl compounds decreased and the yields of unsaturated hydrocarbons showed a fluctuant trend. The undesirable aromatic compounds were only detected at 600 °C and 650 °C. As the heating rate increased, the yields of carbonyl compounds increased, while the yields of unsaturated hydrocarbons decreased. The possible fast pyrolysis pathway of palm oil showed that palm oil underwent a series of parallel reactions and continuous reactions to form the final products. The most suitable reaction conditions of palm oil pyrolysis should be further determined by the production purpose and detailed technical and economic analysis. [ABSTRACT FROM AUTHOR]

The Adaptive Boosting (AdaBoost) algorithm is a widely used ensemble learning framework, and it can get good classification results on general datasets. However, it is challenging to apply the AdaBoost algorithm directly to imbalanced data since it is designed mainly for processing misclassified samples rather than samples of minority classes. To better process imbalanced data, this paper introduces the indicator Area Under Curve (AUC) which can reflect the comprehensive performance of the model, and proposes an improved AdaBoost algorithm based on AUC (AdaBoost-A) which improves the error calculation performance of the AdaBoost algorithm by comprehensively considering the effects of misclassification probability and AUC. To prevent redundant or useless weak classifiers the traditional AdaBoost algorithm generated from consuming too much system resources, this paper proposes an ensemble algorithm, PSOPD-AdaBoost-A, which can re-initialize parameters to avoid falling into local optimum, and optimize the coefficients of AdaBoost weak classifiers. Experiment results show that the proposed algorithm is effective for processing imbalanced data, especially the data with relatively high imbalances. [ABSTRACT FROM AUTHOR]