In this study, the viscometer is used to evaluate the viscosity of slag containing 10% SiO
2
with varying CaO/Al
2
O
3
ratios. When CaO/Al
2
O
3
ratio increases in the 3.00–4.00 range, the viscosity ...exhibits a non‐monotonic behavior characterized by an initial decrease followed by an increase, with a minimum value of 0.046 Pa·s observed at 1673 K. The slag with a CaO/Al
2
O
3
ratio above 3.00 has relatively low and stable viscosity within the range of 1373–1673 K, which is beneficial for slab quality of high‐aluminum steel. X‐ray diffraction and Raman spectroscopy are used to better understand the viscosity evolution of slag containing 10% SiO
2
. A higher CaO/Al
2
O
3
ratio depolymerizes network structures due to the breaking effect of free oxygen O
2−
. Upon surpassing a CaO/Al
2
O
3
ratio of 3.50, the transformation of the crystallization phase occurs from CaO·SiO
2
to 2CaO·SiO
2
. Additionally, a higher CaO/Al
2
O
3
ratio promotes the precipitation of the 11CaO·7Al
2
O
3
·CaF
2
crystal in the slag.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Bedding-parallel calcite veins (BPCVs) occur widely in Upper Cretaceous lacustrine shales of the Qingshankou Formation in the Northern Songliao Basin, China. Research on the formation processes and ...geological significance of BPCVs has focused on the sources of fluid, timing of formation, initiation, dilation and growth mechanisms, and on relationships with hydrocarbon generation. In this study, we addressed these issues through a comprehensive study of drill cores containing BPCVs using petrographic observations, isotope geochemistry, rare earth element (REE) analysis, fluid inclusion analysis, in situ U–Pb dating, and basin modeling. BPCVs were observed in medium–high maturity shales with high organic matter contents with heterogeneous compositions. Similarities in δ13C, δ18O, 87Sr/86Sr, and REEs contents between BPCVs and the host shale indicate that locally derived formation fluids driven by chemical gradients were involved in BPCV formation. The in situ U–Pb age dating (70 ± 8.9 Ma and 70.6 ± 9.7 Ma) constrained BPCVs formation to the late Cretaceous, corresponding to a burial depth of ∼1600 m, indicating that the BPCVs formed in the oil window. The latter is also supported by fluid inclusions-derived temperatures (∼76–109 °C). BPCV formation included vein initiation and dilation, and the microstructures, e.g., domal and pincer structures, sigmoidal calcite veins, conjugate en-échelon calcite vein arrays, as well as mechanical crystal twins of the BPCVs, all indicate that tectonic compression influenced fracture development as also indicated in other basins where beef occur. Fluid overpressure caused by hydrocarbon generation, tectonic compression, and clay mineral transformation (mainly smectite to illite conversion) was responsible for vein dilatation. Antitaxial fibrous crystals with smooth crystal boundaries and high aspect ratios, containing sinusoidal solid inclusions as well as median planes, indicate that crystallization force promoted vein growth. Thus, BPCVs can be used as a good indicator of hydrocarbon generation, and horizontal tectonic compression.
•Bedding-parallel calcite veins (BPCVs) occur widely in medium–high maturity lacustrine shales of the Songliao Basin.•Locally derived formation fluids driven by chemical gradients were involved in BPCV formation.•The in situ U–Pb age dating indicates that the BPCVs formed in the oil window.•Tectonic compression influenced fracture development, and crystallization force promoted BPCV growth.•BPCVs can be used as a good indicator of hydrocarbon generation, and horizontal tectonic compression.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
In order to avoid the complicated control and fussy procedure associated with foreign species and templates in conventional synthesis strategies, a simple reactant conversion-intercalation strategy ...is developed to synthesize interlayer-expanded MoS
2
(E-MoS
2
) by employing ammonium thiocyanate converted from a thiourea reactant as intercalator. In this strategy, the thiourea plays a bifunctionality role as reactant and intercalator precursor to ensure
in situ
embedding into the interlayers of MoS
2
to expand the interlayer spacing. The optimal E-MoS
2
obtained presents superior supercapacitor performance with a specific capacity of 246.8 F g
−1
at 0.5 A g
−1
in 1 M Na
2
SO
4
electrolyte in a three-electrode system, outperforming pristine MoS
2
prepared by a conventional hydrothermal method (42.5 F g
−1
at 0.5 A g
−1
). Furthermore, a symmetric supercapacitor based on an E-MoS
2
electrode delivers a high specific capacity of 261.3 F g
−1
and energy density of 13.3 W h kg
−1
at 0.5 A g
−1
, and excellent cycling life with 81.7% capacity retention after 3000 cycles at 2 A g
−1
. Density functional theory calculations reveal that the NH
4
+
and SCN
−
can be effectively adsorbed on the surface to be inserted into the interlayers during the growth of MoS
2
, resulting in an expanded interlayer spacing of 9.4 Å, and the favorable electrochemical performance stems from the large Na
+
adsorption capacitance and low diffusion barrier of the E-MoS
2
. This work offers a novel intercalation strategy that may be generally applicable to other layer-structured materials, shedding some light on the development of high-performance electrode materials
via
interface engineering for energy applications.
A novel reactant conversionintercalation strategy is proposed to synthesize interlayer-expanded MoS
2
with superior supercapacitor performance, which avoids the complicated control associated with foreign species in conventional synthesis strategies.
In order to avoid the complicated control and fussy procedure associated with foreign species and templates in conventional synthesis strategies, a simple reactant conversion-intercalation strategy ...is developed to synthesize interlayer-expanded MoS
(E-MoS
) by employing ammonium thiocyanate converted from a thiourea reactant as intercalator. In this strategy, the thiourea plays a bifunctionality role as reactant and intercalator precursor to ensure
embedding into the interlayers of MoS
to expand the interlayer spacing. The optimal E-MoS
obtained presents superior supercapacitor performance with a specific capacity of 246.8 F g
at 0.5 A g
in 1 M Na
SO
electrolyte in a three-electrode system, outperforming pristine MoS
prepared by a conventional hydrothermal method (42.5 F g
at 0.5 A g
). Furthermore, a symmetric supercapacitor based on an E-MoS
electrode delivers a high specific capacity of 261.3 F g
and energy density of 13.3 W h kg
at 0.5 A g
, and excellent cycling life with 81.7% capacity retention after 3000 cycles at 2 A g
. Density functional theory calculations reveal that the NH
and SCN
can be effectively adsorbed on the surface to be inserted into the interlayers during the growth of MoS
, resulting in an expanded interlayer spacing of 9.4 Å, and the favorable electrochemical performance stems from the large Na
adsorption capacitance and low diffusion barrier of the E-MoS
. This work offers a novel intercalation strategy that may be generally applicable to other layer-structured materials, shedding some light on the development of high-performance electrode materials
interface engineering for energy applications.
Manganese-based materials are considered as the most promising cathodes in aqueous zinc ion battery due to their low cost, high energy density, and non-pollution. To obtain an excellent cathode with ...a potential for commercialization, it is very significant to convert commercial manganese-based materials to superior electrodes through a simple method. Herein, a simple acid etching is used to obtain commercial MnCO3 with porous structure. In situ electro-activation of commercial MnCO3 is performed, and the gradual transformation from inactive MnCO3 particles to active Mn2O3 and γ-MnO2 nanosheets is displayed by ex situ tests. The porous structure induced by acid etching is beneficial to the activated process and the pseudocapacitive storage. The enhanced capacitive process and charge transfer improve Mn dissolution during cyclic test. Meanwhile, ex situ analyses reveal the high reversibility of Zn2+/H+ storage. Significantly, the optimized electrode offers a high reversible capacity of 200 mA h g−1 at 0.05 A g−1 and a long cyclic life with 81/45 mA h g−1 at 0.5/2 A g−1 over 1200 cycles. This work proves the possibility of turning commercial material into outstanding electrode.
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•A simple acid etching is used to obtain commercial MnCO3 with porous structure.•In situ electro-activation of commercial MnCO3 is revealed via ex situ tests.•Ex situ analyses reveal the high reversibility of Zn2+/H+ storage.•Dominant capacitive process improves Mn dissolution.•The porous MnCO3 displays high capacity and long cyclic life.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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•A molten salt method is used to prepare high-crystallized K+-doped LiMn2O4.•The K+ doping improves the structural stability and charge transfer.•The Li3PO4 coating layer prompts the ...interfacial stability and Li+ transfer.•The enhanced rate and cyclic performances are obtained.
The obtainment of low-cost, easily prepared and high-powered LiMn2O4 is the key to achieve its wide application in various electronic devices. In this work, a mild and easily scaled molten salt method (KCl@LiCl) is utilized to convert commercial MnO2 to the high-performance LiMn2O4. At the same reaction temperature, the molten salt method leads to the formation of K+-doped LiMn2O4 with higher crystallinity compared to the conventional solid state method, which contributes to the improved inner charge transfer. The Li3PO4 protective layer is coated on the surface of K+-doped LiMn2O4 to elevate the interfacial stability and the Li+ transfer on interface. Thus, the optimized electrode shows a higher specific discharge capacity (103/60 mAh g−1 at 0.02/2 A g−1) and a longer cyclic life (80 mAh g−1 after 500 cycles at 0.5 A g−1) compared to those of LiMn2O4 by solid state method (49/2 mAh g−1 at 0.02/2 A g−1 and 20 mAh g−1 after 500 cycles at 0.5 A g−1).
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Perennial ryegrass (Lolium perenne L.) refers to a vital species of grass grown extensively as a biofuel and biochemical production across temperate regions. However, both low temperature (LT) and ...high temperature (HT) conditions are unfavorable for the development of this species, causing reduced forage yield. Arbuscular mycorrhizal (AM) fungi are recognized for promoting host plants’ resistance to abiotic stresses via different mechanisms. However, the mechanism underlying the alleviation of plant damage induced by high-temperature stress and low-temperature stress by AM fungi remains to be elucidated so far. Therefore, the current work attempted to explore how the symbiosis with AM fungus Rhizophagus irregularis (R. irregularis) affects the antioxidant activity and hormone levels in ryegrass under LT and HT stresses and reveals the molecular mechanisms. In addition, the contents of non-enzymatic antioxidants, and hydrogen peroxide (H2O2), the activities of antioxidant enzymes, the genes encoding antioxidant enzymes, and the endogenous hormone-related genes in the perennial ryegrass inoculated with or without R. irregularis were analyzed upon exposure to LT and HT stresses. The results showed that inoculating AM plants with R. irregularis alleviated growth inhibition caused by LT and HT stress, as evidenced by significantly higher plant height, shoot and root dry weight, leaf chlorophyll and carotenoid content, net photosynthesis rate, and photochemical efficiency (Fv/Fm) in comparison to non- mycorrhizal (NM) plants under LT and HT stress. Under LT and HT conditions, AM symbiosis decreased electrolyte leakage (EL), malondialdehyde (MDA), H2O2, and abscisic acid (ABA) contents while significantly increasing the activities of our analyzed enzymes (with the exception of peroxidase (POD) in shoots and ascorbate peroxidase (APX) in roots), AsA/DHA and GSH/GSSG ratio, gibberellic acid 3 (GA3), jasmonic acid (JA) and indoleacetic acid (IAA) contents in shoots and roots. R. irregularis inoculation significantly upregulated almost all genes encoding antioxidant enzyme we tested (except for LpGPX1, LpGPX3, and LpGR in shoots, which were unaffected by AM symbiosis in 3d LT treatment) and some related genes in JA biosynthetic pathway, gibberellin synthesis as well as auxin transport and signaling while down-regulated the biosynthesis and signaling genes involved in ABA.
In general, the findings suggested that AM symbiosis regulated the antioxidant defense and the hormone levels in ryegrass, which consequently alleviated the temperature stress-induced plant inhibition.
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•AMF increased the biomass of ryegrass under temperature stress.•AMF enhances the antioxidant defense system of ryegrass under temperature stress.•Hormones and antioxidant systems together regulate temperature resistance in ryegrass.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
•The in-situ stress profile of sandstone-shale interbedded shale oil is obtained.•Propagation of hydraulic fractures in the sandstone-shale interbedded anisotropy model is modeled.•Different ...influence factors on hydraulic fracturing propagation are studied.
The vertical production layer of a shale oil reservoir in the Songnan Region, China, is mainly sandstone-shale interbed, and the reservoir thickness is uneven. As a result of varying interlayer properties, the hydraulic fracture height is hard to increase, and the propagation pattern of the fracture is unclear. In this paper, features of sandstone-shale lithological combination in the Songnan Region were explored by indoor rock mechanics experiments, which clarified the rock mechanics parameters and characterized the anisotropic features. Combined with the well-logging curves, the dynamic and static elastic moduli, Poisson's ratio, and tectonic coefficient were obtained. An evaluation model for crustal stress in the Songnan Region of China was built based on the hydraulic fracturing data. Additionally, a numerical model for 3D propagation of hydraulic fracture was established based on the finite element method to obtain three forms of fracture propagation and the effects of eight parameters, including fracturing fluid injection rate, interface strength, vertical stress, horizontal stress, elastic modulus, etc., on the height and length of hydraulic fracture were investigated. The results showed that increased viscosity and vertical stress of fracturing fluid could effectively increase fracture propagation height, low interface strength, fracturing fluid injection rate, and maximum and minimum horizontal principal stresses, thus favoring the propagation of hydraulic fractures. This study provides some guidance for the efficient development of sandstone-shale interbedded reservoir fracturing.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Abstract
Under the action of natural erosion, the strength, durability and other safety performance of structures and elements gradually decrease with time, which has a great impact. To solve the ...above problem, a series of time-dependent reliability analysis methods were proposed. Based on different structural performance functions, this paper analyzes and discusses different time-dependent reliability theories, including outcrossing-based reliability method, Monte Carlo simulation method, extremum method and other new methods proposed in recent years, which provides reference for later research.
This article focuses on the issue of novel dynamic event-triggered consensus control of multiagent systems (MASs) with denial-of-service (DoS) attacks. Different from the conventional Markovian ...switching topologies, the generally uncertain semi-Markovian (GUSM) switching topologies with partially unknown elements and time-dependent uncertainties are constructed for the leader-following MASs by considering the equipment performance and external uncertain environment influence. To save communication resources, the novel dynamic memory event-triggered strategy (DMETS) is presented to decrease the frequency of communication between agents. Some secure consensus control criteria are established for the MASs with GUSM switching topologies and DoS attacks due to the potential system communication disruption caused by attackers. Finally, two physical system examples are designed to prove the effectiveness of the presented method.
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