Accurate water holdup measurement in oil–water flows remains challenging due to flow-regime-dependent dielectric distributions and the limited sensitivity of conventional amplitude- or phase-based sensing features. This paper proposes a curved microstrip transmission-line sensor that jointly exploits broadband scattering responses and resonance-frequency shifts to characterize water holdup. The curved geometry increases the effective electrical length within a compact footprint, strengthens field interaction with the surrounding medium, and introduces resonance behavior within the operating band. To improve the physical consistency of numerical modeling, the frequency-dependent complex permittivity of oil–water mixtures is experimentally measured using an open-ended coaxial probe and directly incorporated into full-wave electromagnetic simulations. Both emulsion and stratified oil–water conditions are investigated through simulation and experimental validation. The results show that, under emulsion conditions, the magnitude and phase of S11 and S21 exhibit clear monotonic responses to water holdup. Under stratified conditions, conventional magnitude and phase features exhibit reduced resolution due to the spatially non-uniform dielectric distribution. In this case, variations in water holdup primarily modify the interface position rather than the overall dielectric volume, resulting in relatively small perturbations to the effective permittivity experienced by the guided electromagnetic field. Nevertheless, the resonance frequency remains highly sensitive and shifts monotonically with water holdup. The proposed sensor combines a resonant frequency with broadband magnitude and phase responses, where the resonant frequency provides a stable and reliable indicator across different flow conditions. The results demonstrate the potential of curved microstrip transmission-line structures for compact and reliable water holdup measurement in complex oil–water flow environments.

Fly ash is a massive byproduct of coal combustion that poses significant environmental and disposal challenges. Currently, landfilling remains the predominant method for fly ash management, offering limited resource recovery and posing long-term ecological risks. Here we upcycle fly ash into a family of silicon-modulated FAUtype zeolites that can simultaneously capture volatile organic compounds (VOCs) and CO2. Introducing an external silicon source shifts the crystallization product from SOD to FAU topology. Among the resulting zeolites, FZ-2.5(Si) shows the highest micropore specific surface area of 627.2 m2 & sdot;g-1. This sample achieves the best adsorption performance, with capacities of 4.25 mmol/g for toluene and 6.78 mmol/g for acetone. In situ DRIFTS and temperature-programmed desorption confirm stronger VOCs-framework interactions in FZ-2.5(Si), while higher silicon content enhances hydrophobicity but reduces surface acidity and CO2 uptake. Life cycle assessment reveals that converting fly ash into zeolites reduces environmental impacts by up to 80% compared with landfilling, with FZ-2.5(Si) delivering the greatest benefits in global warming and photochemical ozone potentials. Economically, FZ-2.5(Si) yields a net revenue of approximately 1200 USD/ton, far surpassing the cost of landfill. This work presents A circular strategy upcycles fly ash into high-performance adsorbents via silicon tuning, yielding dual environmental and economic benefits.

As oil and gas reservoirs progress into the mid-to-late stages of development, produced fluids increasingly exhibit high water-cut and complex flow regimes. Conventional water-cut measurement techniques based on capacitance, conductance, and resistance often face challenges in terms of accuracy, stability, and adaptability. In this study, a novel non-contact broadband microwave system, based on a ridged-horn antenna microwave transmission sensor (RHAMTS), is proposed to achieve highly sensitive full-range (0–100%) water-cut monitoring. The RHAMTS consists of two identical ridged-horn antennas, whose geometries are optimized through analytical design calculations and full-wave finite-element simulations. Numerical simulations are first performed to elucidate the sensing mechanism. Subsequently, static and dynamic experiments are conducted under two representative conditions: emulsified oil-water mixtures and stratified oil-water layers. The results indicate that the broadband spectral signatures of the RHAMTS can effectively characterize water-cut in both emulsified mixtures and stratified oil-water layers. For emulsified mixtures, both amplitude attenuation and phase shift vary systematically with water-cut, and the RHAMTS can still effectively characterize water-cut under saline conditions. For stratified oil-water flow, results from both static and dynamic experiments demonstrate that amplitude attenuation provides more robust features for practical water-cut discrimination. Compared with conventional methods, the proposed RHAMTS offers non-contact operation, rich spectral information, and compatibility with various flow regimes, providing a feasible and efficient approach for water-cut monitoring under complex field conditions.

Summary Surfactants are widely added to fracturing fluids to reduce oil–water interfacial tension and enhance oil recovery in tight sandstone reservoirs. However, synthetic surfactants often require high dosages, show limited adaptability to pore-scale heterogeneity, and exhibit weak capability to mobilize residual oil trapped in small pores. Although biosurfactants and bio–synthetic surfactants show promising potential, their pore-scale displacement behavior and underlying mobilization mechanisms in tight sandstones require further systematic investigation. In this study, the oil displacement efficiency and microscopic mobilization mechanisms of the rhamnolipid, bio–synthetic surfactants, and synthetic surfactants are systematically investigated. A series of comparative experiments is conducted, including wettability alteration measurements, the in-situ CT–based relative permeability characterization, and core flooding tests integrated with the in-situ NMR. The evolution of relative permeability curves, contact angles, T₂ relaxation spectra, and T1–T2 two-dimensional maps is analyzed to quantify fluid redistribution and pore-scale oil mobilization during flooding. The results show that bio–synthetic surfactants achieve the highest oil recovery, reaching 40.53% in the in-situ CT flooding tests and 42.12% in the in-situ NMR flooding tests, which is significantly higher than that of the rhamnolipid (31.86% and 35.21%) and synthetic surfactants (31.86% and 33.60%). Bio–synthetic surfactants induce wettability alteration at an early flooding stage, with the contact angle increasing rapidly from 0° to 104.5° within 0.5 h, and exhibit more balanced oil mobilization between large and small pores. NMR T2 spectral analysis shows that the bio–synthetic surfactants maintain high oil mobilization in large pores (45.73%) while significantly enhancing small-pore oil mobilization from 5.20% to 26.45%. Furthermore, T1–T2 maps indicate that only surfactant systems containing rhamnolipid effectively mobilize recalcitrant oil adsorbed on pore surfaces. These results demonstrate that the synergistic combination of biosurfactants and synthetic surfactants enhances pore-scale oil mobilization and maximizes sweep efficiency, providing mechanistic insights for the design of high-efficiency fracturing fluid systems in tight sandstone reservoirs.

Histopathological cancer diagnosis conventionally relies on the examination of paraffin-embedded tissues. Terahertz (THz) technology has emerged as a promising avenue for expediting cancer diagnosis. This study focuses on evaluating the complex permittivity of lung cancer tissues in comparison to para-carcinoma tissues embedded in paraffin, utilizing electronic THz technology. The frequency range covers 0.11-1.1 THz, encompassing six independent bands spatially spliced together. The sample's surface was meticulously flattened, and the scattering parameter matrix underwent thorough processing prior to permittivity inversion. Additionally, a specially designed sample fixture is implemented to enhance test accuracy. The empirical findings elucidate a consistent trend wherein the real part of the permittivity of each cancer tissue surpasses that of its corresponding para-carcinoma tissue. This pattern holds true across diverse types and locations of lung cancer sources. The deleterious impact of water-induced absorption of THz waves is mitigated through paraffin filling in tissue pores. Consequently, this reveals the nuanced influence of compositional and microstructural disparities between cancer and para-carcinoma tissues. The cancerous lesion induces alterations in the types and content of amino acids within the tissue samples. Leveraging the effective medium theory model to fit the permittivity spectra allows for a comprehensive representation of these discernible differences.

Microwave dielectric properties serve as critical diagnostic parameters in geophysical studies, enabling quantitative evaluation of factors such as water saturation and matrix structure. Open-ended coaxial probes (OCP) are widely used for broadband microwave dielectric measurements in highly mineralized loose geophysical sample like soil, sediments etc., where electrode polarization (EP) effects severely degrade measurement accuracy and obscure the Maxwell-Wagner (M-W) polarization near the lower frequency limit of OCP. Notably, the EP effect is highly sensitive to the electrode surface, and variations in the measurement process can significantly impact the accuracy of the EP correction model. To address these issues, this study proposes an optimized EP correction method based on the constant phase angle element (CPE) model. By calibrating with brine of the same conductivity as the sample after the initial measurement, consistency in electrode surface and conductivity conditions is ensured. This study establishes a transfer mechanism between the two scenarios, effectively removing EP's impact on complex permittivity measurements below several hundred MHz in highly mineralized sediment. Experimental results on artificial sediments revealed that M-W polarization strength increases with decreasing sand particle size, and with increasing brine mineralization and saturation. Additionally, clays with high cation exchange capacity enhance dispersion below 100 MHz and shift it to higher frequency. Further measurements on hydrate reservoir marine sediment confirm the method's effectiveness in complex natural samples. By eliminating the interference of EP, this study provides a reliable solution for accurate dielectric measurements in highly mineralized sediment, offering significant value for investigating seafloor sediments and soils.

Terahertz technology has demonstrated significant potential for biomedical applications, particularly in tumor identification. Investigating the fundamental principles of terahertz-based tissue discrimination provides crucial theoretical foundations for developing THz imaging diagnostics and pathological analysis platforms. Current technical limitations, including constrained dynamic range and insufficient detection sensitivity, have hindered comprehensive characterization of tumor dielectric properties, particularly regarding statistically significant patterns and their pathological correlations. This study implemented a solid-state electronic terahertz system with multi-band stitching technology, achieving sensitive dielectric characterization across 0.11-1.1 THz. A total of 39 paired cancer and normal tissue samples from five organs (lung, kidney, colon, stomach, and breast) and two histological subtypes (adenocarcinoma and squamous carcinoma) were analyzed. Paraffin embedding was utilized to eliminate free water interference and improve detection sensitivity to intrinsic tissue properties, particularly specific protein content. Macroscopic statistical analysis revealed that cancer tissues exhibited consistently higher complex permittivity values compared to matched normal tissues, with a mean elevation of 0.135 and reduced data dispersion. Preliminary findings from in-depth microscopic pathological evaluation of nine lung cancer specimens revealed distinct correlation patterns: PD-L1 expression showed an exponential relationship while Ki-67 exhibited linear proportionality with tumor-normal permittivity differences in the real component. Combined with ultrastructural characterization, these dielectric disparities are attributed to tumor-induced changes in cellular density and overexpression of specific proteins. This work preliminarily establishes a quantitative association between terahertz dielectric responses and oncological biomarkers in lung cancer, providing important experimental evidence for advancing THz-based tumor analysis and diagnostic protocol development.

Catalytic gasification can obviously accelerate gasification reaction rate. However, recovery of catalysts is currently the main challenge. In this work, a kind of industrial solid waste called red mud was tested as a disposable catalyst for coal gasification and its catalytic behaviors were preferentially investigated. The results show that red mud has well-developed pore structures. A variety of catalytic species were found in it and more active sites were formed, consequently resulting in outstanding catalytic ability. Gasification temperature, O/C ratio, and steam flow rate are suggested to be key points influencing the gasification process. Under the same conditions (950 degrees C, O/C ratio: 3, and steam flow: 0.05 mL/min), carbon conversion, syngas selectivity, and syngas yield of coal gasification catalyzed by red mud reached up to 83.7 %, 88.6 %, and 119.0 mol/g, respectively, which were enhanced by 21.0 %, 22.5 %, and 2.4 % compared with that using pure Fe2O3. XRD and XPS analyses proved that in the early reduction process, the lattice oxygen gradually dissociated from inside of Fe2O3 crystals and migrated to the outside surface to react with char and reducing gases, leading to the formation of Fe3O4 and Fe. Subsequently, with continuous addition of steam, Fe was oxidized to regenerate Fe3O4 and the oxidation-reduction performance of Fe was hence improved.

Red mud (RM) contains a high content of Fe2O3, which provides an ample supply of acid sites and moderate reducibility. These properties have made RM a viable candidate for catalytic reactions such as the selective catalytic reduction of NOx. However, the inert nature of surface oxygen species limits its application in catalytic oxidation. Here we report that the MnOx introduction reconstructs the surface electronic structure of RM and activates the key oxygen species efficiently. The synthesized Mn-doped acid-pretreated RM (Mn/ARM) catalyst exhibited excellent low-temperature toluene oxidation activity, in which T90 (temperature at which 90 % toluene conversion is achieved) decreased by 26 degrees C and 37 degrees C compared to that of conventional Mn/TiO2 and Mn/Al2O3 catalysts, respectively. The comprehensive characterization results revealed that the strong Fe-Mn interaction results in an enhanced electron transfer by Mn4+ + Fe2+ Mn3+ + Fe3+. The reconstruction of the surface electronic structure not only activated the chemisorbed oxygen over Fe2O3 but also enhanced the mobility of lattice oxygen of MnOx. The in-situ diffuse reflectance infrared Fourier transform spectra further revealed that the improvement mechanism, in which the active chemisorbed oxygen species accelerated the toluene adsorption and methyl group activation, and the enhanced lattice oxygen are responsible for the aromatic ring breakage during deep oxidation. Findings from this study provide valuable insights for the high-value utilization of solid waste and low-cost substitution of commercial environmental catalysts.

Enriching oxygen species in perovskite catalysts provides more active sites for the catalytic oxidation of air pollutants, but its further application in environmental chemical engineering is still constrained by the inherent lack of oxygen species reactivity and the difficulty of replenishing depleted oxygen species. Herein, we present a scalable one-pot strategy for the in situ fabrication of a homogeneously distributed heterostructure, which brings La2CuO4 perovskite a 58-fold activity enhancement and robust antisintering/water/coke in toluene oxidation, higher than currently reported perovskite catalysts. Superior to the single "oxygen enrichment" effect of conventional surface-aggregated heterostructures, the homogeneously distributed heterostructures induce the reactivity enhancement of adsorbed oxygen and the backfilling/replenishment of depleted lattice oxygen, which break through the rate-determining steps of the low-temperature Langmuir-Hinshelwood and the high-temperature Mars-van Krevelen mechanisms, respectively. The scalability has been demonstrated in broader perovskite systems and for oxygen evolution reaction, offering a more dependable oxygen supply for environmental catalysis.

This paper conducts a detailed study on a non-contact feeding method for terahertz (THz) coplanar waveguides based on ultra-wideband antennas. For the THz frequency band, the size of electromagnetic devices has reached the micrometer level. Researchers usually use two sets of contact THz probes to feed dual-port wideband devices such as coplanar waveguides. However, the mechanical vibration of the probes can introduce unknown phase errors during the measurement process, affecting the repeatability of phase measurements. Moreover, due to the lack of a reliable probe contact feedback mechanism, the insertion loss of the device during the measurement process is difficult to quantify with high precision. Therefore, contact probes must be combined with high-precision measurement equipment and complex post-processing algorithms to achieve effective feeding of dual-port devices, resulting in high application costs for dual-port devices. Therefore, this paper explores a THz coplanar waveguide feeding technology using a hexagonal planar slot ultra-wideband antenna. The non-contact feeding structure mainly adopts a hexagonal planar slot broadband antenna, which has a simple structure, low processing difficulty, and a wide operating bandwidth. Simulation results show that this antenna is suitable for a parallel dual-horn antenna optical path and can achieve a high receiving efficiency for THz coplanar waveguides in the 1.0-1.5 THz frequency band, with a comprehensive insertion loss of approximately 10dB, meeting the expected design goals. This method realizes a repeatable, low-cost, and easy-to-operate noncontact feeding solution for integrated circuit devices and has great application prospects in the field of THz device design research.

Broadband dielectric logging provides high resolution and strong anti-interference capability, yet existing tools struggle to balance bandwidth and accuracy, adapt to harsh downhole conditions, and maintain a compact structure suitable for stable field deployment. To address these limitations, a novel broadband dielectric logging approach based on spoof surface plasmon polaritons (SSPP) transmission lines is proposed. First, a cylindrical metallic SSPP transmission line with periodic surface grooves is designed to meet the detection requirements of hydrate-bearing formations. Owing to the slow-wave characteristics and surface-concentrated field distribution of SSPP waves, the proposed structure enables direct surface-sensitive measurements, while its monolithic cylindrical geometry facilitates integration with conventional logging tools and helps mitigate practical issues such as tool sticking and mud blockage. Then, through dispersion analysis and structural optimization, a wideband low-loss excitation scheme is established to ensure efficient SSPP propagation. Finally, the broadband dielectric properties of hydrates are theoretically analysed, and a complete downhole detection system is constructed. Experimental characterization of hydrates with varying water content demonstrates that the $S$21 phase exhibits an apparent monotonic variation and maintains high sensitivity; at individual frequencies, phase differences accurately capture changes in water saturation. Compared with traditional microstrip-based methods, the SSPP transmission line achieves a significantly larger phase response. Overall, the proposed SSPP-based dielectric logging tool demonstrates broadband, highly sensitive, and structurally robust performance. Its excellent adaptability and integration potential make it a promising solution for natural gas hydrate monitoring and for identifying water-flooded formations in oilfield applications.

The catalytic volatile organic compound oxidation poses a dilemma for perovskite (ABO3) catalysts, as their high lattice oxygen reactivity (electron-deficient O-(2-x)) depends on attracting coordinated oxygen electrons through an increased electronegativity of B-site cations, but this impedes the healing of oxygen vacancies and thus results in a low concentration of active lattice oxygen due to the limited O2 dissociation in electron-deficient environments. Herein, we compress [Co/MnO6] octahedra through A-site Cs+ doping in the double perovskite (La2CoMnO6-σ), which optimizes the orbital hybridization between Co/Mn 3d and O 2p. This promotes electron transfer from O to Co/Mn while reducing Co/Mn electronegativity, resulting in a synergistic improvement of lattice oxygen reactivity and oxygen vacancy healing. As a result, La1.70Cs0.30CoMnO6-δ exhibits a remarkable 30.2-fold and 4.5-fold increase in toluene oxidation rates at 200 °C compared to LaMnO3 and La2CoMnO6-σ, respectively, surpassing the reported Co/Mn-based perovskites. Due to its ultrahigh lattice oxygen reactivity and abundant active lattice oxygen, benzaldehyde intermediates predominantly governed by adsorbed oxygen are synchronously oxidized to CO2 and H2O by lattice oxygen, enabling Mars-van Krevelen reactions to function efficiently coupled with Langmuir-Hinshelwood reactions. This work harmonizes the reactivity and abundance of lattice oxygen, offering a robust strategy to advance the development of high-performance perovskite catalysts for catalytic oxidation.

Natural siderite modified TiO2 (Sid/TiO2) catalyst was prepared by coprecipitation method, and the Sid/TiO2 prepared under optimized conditions was loaded on ceramic filter tube (ST-CFT) through impregnating method. The results showed Sid (0.3)/TiO2 (450) catalyst had the best denitrification effect when the mass ratio of siderite was 0.3 and the calcination temperature was 450 degrees C. The NOx conversion efficiency reached more than 95 % at reaction temperature was 275-350 degrees C when NO initial concentration of 500 ppm, and gas hourly space velocity (GHCV) for 36,000 h- 1 . While the catalyst's median particle size (d50) was 5.3 mu m, the slurry concentration was 7.5 wt%, and the face velocity (FV) was 1.5 m/min, NOx conversion efficiency of the ST (4)-CFT (7.5) reached 100% at reaction temperatures ranging from 275 to 375 degrees C. It also revealed excellent water, sulfur, and alkali resistance. Compared with pure siderite catalyst, the crystallinity of active component alpha-Fe2O3 was decreased by introducing Ti carrier, and the utilization efficiency and dispersibility of the active center were improved. The synergistic effect of Fe and Ti improved the acid center density and Br & oslash;nsted acid content of the catalyst, which promoted low-temperature SCR performance.

Hydrate saturation (Sh) is one of the key parameters for resource assessment of hydrate reservoirs and production optimization of natural gas. There are still significant challenges in determining the Sh in clayey formations. Both dielectric and resistivity logging tools have been used for identifying and evaluating hydrate-bearing formations; however, there is little work on a joint analysis and modelling of the permittivity and resistivity for quantifying the Sh. To bridge the knowledge gap, we have proposed a novel permittivity-conductivity (P–C) joint approach based on TDR (time domain reflectometry)-derived parameters (i.e., apparent permittivity Ka and bulk conductivity σdc) in this work. The proposed P–C joint approach can provide a theoretical basis for the joint interpretation of dielectric and resistivity geophysical measurements on hydrate-bearing formations in the field. First, the basic theory for deriving the Ka and σdc from the TDR responses of hydrate-bearing sediments was formulated based on the dielectric polarization and electrical conduction mechanisms. Second, an experimental campaign was carried out including the development of experimental system, calibration of TDR probe and design of experimental scheme. Third, the influences of hydrate saturation, clay mineralogy and clay content on the TDR responses of unconsolidated sediments were examined. Then the Ka and σdc were related to Sh respectively, and finally a novel P–C joint model for the quantification of Sh in clayey sediments was established and verified. It has been demonstrated that: (1) the Ka of the clayey samples with hydrates decreases almost linearly with an increasing clay content up to 20 %, while the σdc of the smectite-bearing samples decreases nonlinearly in contrast to the linear trend for illite; (2) the power-law mixing formula incorporating an empirical exponent is a preferable permittivity model for hydrate-bearing clayey sediments due to its merits of empirical and theoretical nature, while the Simandoux equation is effective to account for the clay effects on the conductivity of hydrate-bearing sediments with smectite and illite; (3) the P–C joint model can be established by utilizing the porosity of hydrate-bearing sediments as a bridge parameter between Ka and σdc. The variation behavior of Ka and σdc with different types and contents of clay minerals can be explained by the difference of the amount of bound water and swelling effects between the illite-bearing and smectite-bearing samples. The proposed P–C joint model outperforms the standalone permittivity-based and conductivity-based models especially for the clayey cases. The root-mean-squared errors of the P–C joint models are 7.339, 2.930 and 2.065 % for the clean-sand samples, clayey samples with illite and smectite, respectively.

The traditional design method for terahertz metasurface biosensors is cumbersome and time-consuming, requires expertise, and often leads to significant discrepancies between expected and actual values. This paper presents a novel approach for the fast, efficient, and convenient inverse design of THz metasurface sensors, leveraging convolutional neural network techniques based on deep learning. During the model training process, the magnitude data of the scattering parameters collected from the numerical simulation of the THz metasurface served as features, paired with corresponding surface structure matrices as labels to form the training dataset. During the validation process, the thoroughly trained model precisely predicted the expected surface structure matrix of a THz metasurface. The results demonstrate that the proposed algorithm realizes time-saving, high-efficiency, and high-precision inversion methods without complicated data preprocessing and additional optimization algorithms. Therefore, deep learning algorithms offer a novel approach for swiftly designing and optimizing THz metasurface sensors in biomedical detection, bypassing the complex and specialized design process of electromagnetic devices, and promising extensive prospects for their application in the biomedical field.

Clays have considerable influence on the electrical properties of hydrate-bearing sediments. It is desirable to understand the electrical properties of hydrate-bearing clayey sediments and to build hydrate saturation ( S h ) models for reservoir evaluation and monitoring. The electrical properties of tetrahydrofuran-hydrate-bearing sediments with montmorillonite are characterized by complex conductivity at frequencies from 0.01 Hz to 1 kHz. The effects of clay and S h on the complex conductivity were analyzed. A decrease and increase in electrical conductance result from the clay-swelling-induced blockage and ion migration in the electrical double layer (EDL), respectively. The quadrature conductivity increases with the clay content up to 10% because of the increased surface site density of counterions in EDL. Both the in-phase conductivity and quadrature conductivity decrease consistently with increasing S h from 0.50 to 0.90. Three sets of models for S h evaluation were developed. The model based on the Simandoux equation outperforms Archie’s formula, with a root-mean-square error ( E RMS ) of 1.8% and 3.9%, respectively, highlighting the clay effects on the in-phase conductivity. The frequency effect correlations based on in-phase and quadrature conductivities exhibit inferior performance ( E RMS = 11.6% and 13.2%, respectively) due to the challenge of choosing an appropriate pair of frequencies and intrinsic uncertainties from two measurements. The second-order Cole-Cole formula can be used to fit the complex-conductivity spectra. One pair of inverted Cole-Cole parameters, i.e. , characteristic time and chargeability, is employed to predict S h with an E RMS of 5.05% and 9.05%, respectively.

Recovering massive hydrates in pore-filling morphology deposited in silty-clayey sediments is significant for global long-term clean energy requirements. However, hydrate dissociation leads to sediment strength attenuation and reservoir deformation, thereby endangering reservoir and wellbore safety. To ensure safe and sustainable hydrate production, more efforts need be made to comprehensively investigate the mechanical behavior of such reservoirs. In this study, a series of triaxial shearing tests were launched on artificial hydrate-bearing silty-clayey sediments (HBSCSs) containing hydrates in pore-filling morphology, and the relevant mechanical behaviors of HBSCSs were obtained and discussed. The strength indication of HBSCSs is revealed to elevate evenly with hydrate saturation from results, while the strength growth amplitude of this material due to pore-filling hydrate (PFH) is much smaller than that due to cementing hydrate reported in previous studies. The strength increment of silty-clayey sediments induced by PFH presence is mainly due to the enhancement in the friction property of this material. The deformation behaviors of HBSCSs are affected by the combination of the initial consolidation degree, the hydrate pore-filling effect and the effective stress. Further advances are awaited to be made about the studies of silty-clayey reservoirs deposited with hydrates in pore-filling morphology.

Resistivity inversion plays a significant role in recent geological exploration, which can obtain formation information through logging data. However, resistivity inversion faces various challenges in practice. Conventional inversion approaches are always time-consuming, nonlinear, non-uniqueness, and ill-posed, which can result in an inaccurate and inefficient description of subsurface structure in terms of resistivity estimation and boundary location. In this paper, a robust inversion approach is proposed to improve the efficiency of resistivity inversion. Specifically, inspired by deep neural networks (DNN) remarkable nonlinear mapping ability, the proposed inversion scheme adopts DNN architecture. Besides, the batch normalization algorithm is utilized to solve the problem of gradient disappearing in the training process, as well as the k -fold cross-validation approach is utilized to suppress overfitting. Several groups of experiments are considered to demonstrate the feasibility and efficiency of the proposed inversion scheme. In addition, the robustness of the DNN-based inversion scheme is validated by adding different levels of noise to the synthetic measurements. Experimental results show that the proposed scheme can achieve faster convergence and higher resolution than the conventional inversion approach in the same scenario. It is very significant for geological exploration in layered formations.

The impact of water on catalyst activity remains inconclusive due to its dependence on the specific reaction environment. To maximize the exploitation of water's promoting effect, we employed ammonia selective catalytic reduction (NH3-SCR) as a probe reaction and proposed a phosphorus modification strategy for Cu-ZSM-5 catalysts. The objective of this approach was to construct water-adaptive microstructures through directional arrangement. To investigate the effect of phosphorus on the transformation of framework copper sites in humid environments, we conducted comprehensive characterizations and density functional theory calculation. Results reveal that water molecules cleave the oxygen bridges between phosphorus oxide and copper, leading to the formation of active isolated [Cu(OH)]+ groups and phosphate. The phosphate species weaken the interaction between exchanged Cu2+ groups and the zeolite framework, leading to the generation of highly migratory hydrated Cu2+ species. This work will potentially guide the rational design of water-adaptive catalysts for gas pollution abatement in a humid environment.